Corlagon

Set Enhancements can be Attuned, which means they level up with you. You can simply get them from the Auction House. Check the wiki for details. Enhancement Unslotters and Enhancement Converters are also noteworthy. Oh, and most people seem to form their own single-player SGs nowadays.

The wiki currently implies it is open to everybody on all Homecoming servers, not just roleplayers. Is that intentional? Would probably be a good thing, not sure whether Ouroboros Portal will be around for much longer.

TOT costume powers are compatible with Stalker's stealth – I'm on one right now. They don't work with that Pool stealth power, however.

You should get offered a mission from them, usually two. Make sure you're in the city proper, and not in an instance or a co-op zone or anything.

I thought Paragon Studios already wanted to add more Enhancement slots back in the day but couldn't feasibly do so because of the way they were coded?

I had such a faulty mouse, too. It was during Issue 12, I think, when Positron's TF was still a single very long thing. And when there were no Merits yet and a single recipe from an exclusive pool would drop after a TF instead. Guess what I accidentally sold.

Costume and Architect files are saved locally.

Yes, storylines can be considered started even without having actually accepted the first mission, I'm sure I've seen that a lot before. And I'm not aware of any way to cancel them.

Sounds like a bug that I first encountered around 2011. After defeating the required number of enemies, it gives you a door mission in the zone where you are at the moment, which fails if you're already in another door mission. I remember reporting this for two other such multi-part missions back in the day. The devs then changed those two missions so that the hunting had to be done in a specific zone, rather than fixing the actual issue.

They've added it to Pocket D. She just needs to make it through Imperial City alive.

That's a common bug, I think it already existed back when Paragon Studios was still around. I've noticed something like this happening in a regular mission, too, when I was rescuing Ace McKnight the other day.

Ouroboros Portal is still around, too.

Super Jump, or Long Jump as the actual effect appears to be called, helps with movement, too. I managed to get gold (and even a top 5 ranking, to my own surprise) last night with nothing but a version of sprint and the Zero-G Pack on, and probably some weaker enhancements. Of course, I certainly could have saved the fuel by getting Ninja Run or Beast Run on that toon.

Have you tried running around in front of the bank entrance? The robbers should spawn when you pass the right spot.

Just search for channels with "Defiant" in their name, and you should find something. P.S. I'm pretty sure I soloed even more.