Hjarki

Debuffs intended to protect players aren't really all that useful - even on Defenders. In general, the more you need them, the less effective they become. That -5% hit or -8% damage is fine against even con minions. Against a four star AV/GM? They might as well not even exist. Status effects, on the other hand, can be useful. Stone Melee is arguably a better Control set than actual Control sets, with an easily stackable AE Disorient and Mag 4 ST Hold. And, of course, the status effect all Tankers have: Taunt.

I play this combo, albeit in a very different fashion. From Staff Mastery, I take Staff Mastery and set it to Mind. Then I do: Precise Strike (Superior Might of Tanker 4p; Hecatomb proc; another proc) Guarded Spin (Fury of the Gladiator A/D, proc; Obliteration D, proc; Armageddon proc; LotG recharge) Serpent's Reach (Gladiator's Javelin A/D, proc; Apocalypse D, proc; Explosive Strike proc; Perfect Zinger proc) Innocuous Strikes (Armageddon 5p; another proc) I don't take any of the spenders or Mercurial Strike. In a ST fight, I can go PS->GS->PS->SR. For multi-target, I can just rotate the two Cones. Since I Hover, this generally allows me to blanket most spawns. For Bio, I skip Parasitic Aura. I use 2xEradication 3p and 2xMocking Beratement 6p to get enough F/C/E/N to reach incarnate soft-cap in Defensive (and obviously well above regular soft-cap in Offensive). I hard-cap S/L and don't worry much about other resists. 6p Preventative Medicine in Ablative for some more recharge - between my two purple sets, the ATO 4p, Preventative Medicine, the two Mocking Beratement, 5xLotG and Mind, I've got enough recharge for the build. For pools, I take Fighting, Leadership (Maneuvers/Assault), Leaping (Combat Jumping) and Flying (Hover/Fly). I use Psi Mastery (Dominate w/Unbreakable Constraint and Harmonic Mind). While this obviously isn't the maximum possible dps out of the build, it will generally deliver a lot more dps than straight-slotting the offensive powers for damage. Since the AF of melee cones is relatively low, those procs don't perform all that much worse than they would in ST powers (and certainly better than in a PBAoE aura).

For ST, I tend to go AB->HB->AB->WJ->WJ, with Water Jet as heavily proc'd as possible. Dehydrate instead of Hydro Blast is also an option.

You consider asking if you care about perma-PA. perma-PA is primarily of concern for builds that intend on solo'ing AV/GM. They need perma-PA because they don't want gaps in taunt coverage that might expose them to attacks from those AV/GM. However, for most builds, this isn't actually all that important because Phantom Army is simply a damage cooldown.

It also appears he's running a sub-optimal rotation where he's only using ET once (rather than twice). I suspect he also didn't split the ATO minimize the internal recharge on Assassinate (and thus get the maximum proc rate on Hide before TF). In terms of raw non-proc/non-pet ST damage, my experience is that EM Stalkers are in a class all their own.

Dual Blades may be thematically cool but it's one of the weakest overall melee sets in terms of either damage or utility. It is almost directly inferior to the similar Claws. Stone Melee, on the other hand, is one of the strongest melee sets. It has incredibly effective controls - a self-stacking AE Disorient and a Mag 4 Hold - coupled with very strong single target damage.

Generally, the balance tilts towards Corruptors. Vigilance is perhaps the most useless inherent in the game. The damage bonus is largely a way to make Defenders suck less while solo and it isn't even very good at that job because give +damage to the AT with the lowest damage scale in the game isn't very good. I can see why the endurance reduction might seem a good idea - but only if you're thinking about games like WoW rather than CoH. In WoW, the highest resource expenditure for support specs comes when you're healing a lot. In CoH, the highest resource expenditure for support specs comes from their normal blasting rotation. So you're actually get endurance reduction when you need it least. The ATOs are also terrible. The Defender versions get two worthlessly small AE heal/absorb effects on an AT that could already do much better if it chose to do so. In contrast, Corruptors get a purple damage proc and a proc that can help with endurance issues - both useful to have as a regular part of your rotation. There's also the issue that the primary value of the support sets isn't really 'support' so much as a clunky form of armor set for the player themselves. Support affects applied to unknown allies tend to be very inefficient because they so often over-shoot the mark and apply buffs the target doesn't actually need. So having slightly better values so you can over-shoot even more isn't very good while having a lot more damage (50% more damage against an AV/GM) is.

The one I'd want would be to take Demon Summoning, remove all the pet stuff and expand it into a full melee set.

Energy Melee is an interesting set from the standpoint of trying to optimize its output. The best scheme I've found is: Assassin's Strike (Superior Blistering Cold all but proc; Superior Stalker's Guile proc) Total Focus (Superior Stalker's Guile all but proc) Energy Transfer (Hecatomb all but D) Energy Punch (Superior Assassin's Mark) Sniper Attack (Superior Winter's Bite all but proc) Energy Punch Energy Transfer Assassin's Strike is effectively auto-crit (at least on the second and subsequent rotations) because both Energy Transfer and Total Focus have a 100% Focus chance. While Blistering Cold has a bit too much recharge, it still delivers a ~77% proc chance on Hide (which is better than the 67% you'd get from straight-slotting). This gives you almost an 80% chance to generate double Energy Store stacks (making both Energy Transfers the fast version). The hardest part of the rotation is the 315% recharge needed for Energy Punch, but Superior Assassin's Mark provides about 100% of this so you only really need +115% global recharge (not that hard with +20% from secondary). Obviously, additional procs can go into the Sniper Attack (such as Apocalypse) and Energy Transfer. You can also reverse the order on Assassin's Strike and Total Focus if you want one of your Energy Transfer to heal rather than damage. Power Crash can take Armageddon and does a fair bit of damage (it has longer recharge and higher damage for Stalkers). However, you can't really run a double Energy Store rotation very effectively with just the above attacks unless you don't mind standing around doing nothing for various periods of time. That being said, the Energy Store version of Power Crash isn't all that much better than the regular version due to the difficulty of lining up effective Cones (especially without a taunt aura). Energy Aura should be fairly straightforward. You slot uniques, pump up your defenses, etc. Disrupt is a good place to park the 5th purple set for recharge but I don't think it's a very good power. Note that the 'fast' version of the rotation is a bit over 10 secs and will eat a bit over 20 health/sec. Since this about 4x the health regeneration of an unenhanced Stalker, this is not a minor challenge.

Scourge averages out to around 30% more damage against an arbitrarily large health pool. In practice, it varies from a bit less efficient than that to a lot less efficient than that. The issue is that you calculate whether an attack will Scourge before the damage lands. So if you had some hypothetical attack that did 50% of an enemy's health pool, it would never (usefully) Scourge. On the other hand, Rains are famously good with Scourge because each tick is so tiny and you'll get nearly perfect performance. However, as with all such effects, additional effects from set mechanics, DoT and procs cannot Scourge. A Scrapper will generally get about 10% - 15% (depending on ATO and set) additional damage from criticals. However, they get this regardless of the size of attacks or the opponent's health pool so they're going to get generally better performance on non-AV/GM. They're also working off of a much higher base damage scale and melee sets tend to hit a bit harder than blast sets. Stalkers, between the progressive critical chance stacking on Assassinate and periodic hides from ATO, probably get around the same 'crit rate' as idealized Corruptors with, again, a high damage scale and melee sets. In terms of the overall notion of Corruptors (and support AT in general), it's important to remember that CoH is not a competitive game. Even against the most difficult content, you're going to find a lot of 'sub-optimal' play. If I were tasked with putting together an optimal team to deal with the hardest content in the game, it would probably be almost entirely Tankers using sets like Bio, Radiation and Shield. You get great values on the stacking Leadership pools as well as the stacking effects of those armor sets. While no individual player on your team could debuff/buff like an individual support AT, the cumulative effect would be similar without taking the damage hit from the low damage scale AT. However, if you're just recruiting random people from world chat to join your adventure in four-star, you probably want all those support AT to deal with the fact that you don't have that sort of optimized team.

It depends on what I'm building. For 90% hard cap AT, I'm normally building to tank. That means a combination of hard-capped resists, debuff resistance and healing/regen while my defenses are largely just whatever happens between offensive set, pool toggles and enhancement bonuses. For 75% hard cap melee, I'm probably playing a Defense set that soft-caps most typed or all positional and not caring all that much about resists. For squishies, I'm normally looking at either soft-cap Ranged (for purely ranged builds), S/L/E/R or S/L/E (for builds that need to be in melee range from time to time) or R/A positional (almost exclusively on Defenders since they're the only ones who can do this normally). Again, not concerning myself much with resists.

It really depends on the power sets you're looking to play.

Both Blazing Arrow and Explosive Arrow do Fire damage.

Not really, no. However, +10% Recharge and +5% Ranged Defense is fantastic.

While accurate in the abstract, this is not a very useful list in the specific. For example, I'd never prioritize Max HP on a Bio Tanker because you can't. The general method for optimization is to create a cost function that relates the value of various attributes. So you might write 1.7a + 1.2b + 2.9c + 3.2d = optimization parameter. Those weights let you counter-balance the actual impacts rather than simply saying d > a. So let's consider Bio vs. Invulnerability. On an Invulnerability Tanker, I'd almost certainly slot Dull Pain with Preventative Medicine. On a Bio Tanker, I'd rarely ever add a slot to Inexhaustible. While I'd like to maximize Max HP on every Tanker, the reality is that Inexhaustible doesn't return enough value to justify slotting while Dull Pain (about 4 times more effective) does. So when you say to prioritize Max HP on a Bio Tanker, my response is: you can't, so don't bother. The Accolades and Unbreakable Constraint unique that every build takes will be the lion's share of your Max HP because Bio is only marginally better than Super Reflexes at buffing Max HP. Likewise, when you say to prioritize Regen, I'm not going to slot the pair of +regen uniques (or, as noted above, Inexhaustible) because the return on investment for those slots is so small. On the other hand, I'm almost certainly going to slot Ablative Carapace and DNA Siphon because the return is very large for my investment there. But it's not like I'm going to make some sort of radical compromise that hurts my build. I'll go to ID levels using sets that otherwise improve my build. When I look at Bio armor, I'm not inventing a priority list based on what I wish it provided but based on what it - and the various sets - actually provide. So my build goals are more along the lines of reaching F/C/E/N soft-cap (normally just a byproduct of slotting LotG mules and pushing Environmental Modification to ED) and S/L hard-cap (not all that hard but still requires some effort). I'm not thinking about Max HP or Regen at all because those are just simply byproducts of slotting powers in a fairly normal way. I'm not thinking about recharge all that much because most builds land in the 80% - 110% range unless you're really trying to push them for some reason - and going out of that range normally requires some serious compromises. Ultimately, I think the key is to not try to force a build to be something it's not. The almost inevitable result is highly un-optimized build where you sacrifice all sorts of critical elements in single-minded pursuit of something you probably didn't need in the first place.