@Verix
Yes, if you slot Celerity stealth IO into Super Speed, you are definitely 'invisible' to most things. I've never dipped into invisibility for any reason and I don't think you should have to for your Thugs/Time.
I can try to put together my new build for you, its actually my Beast/Time but I can tweak it, they are 99% close to Thugs.
I used to be able to run +4/x8 S/L farms with my Thugs/Time (and I still do with other characters, including my Beast/Time). Time makes that very possible. Time is wonderful.
Yes, I get the most 'bang for my buck' out of Speed/Hasten, then Maneuvers/Tactics, and then Travel Pool of choice (I like Hover/Fly/Afterburner). Right there are three places to slot a LOTG global recharge IO. With Far sight you have a 4th spot. You don't need to pursue a 5th spot for it, as you aren't trying to get Perma Phantom Army or anything and Time gives plenty of extra global.
Temporal Selection is nice but not necessary. If I had room to take it I'd put it on the Brute or the Arsonist. Arsonist does live longer these days due to the AI, but he's still more vulnerable.
Mace is a solid pick. I used to like it, but I have not taken it on any characters since Live. I find Time already boosts Defense a lot and I build for Ranged Defense cap, myself. Melee doesn't matter too much. Your -ToHit from Time's Juncture will make sure to cover the gap to the 'cap' for anything that somehow ignores your pets and goes for you. Plus with all the slows, holds, etc, you don't generally worry about melee. Mace is solid, however. You'd cap out S/L/E easily. But you have no resistances. So when you do get hit, it hurts. Hence, I prefer to cap Ranged (easy enough) and have a resistance shield, such as Mu. Then add in two +3% global Defense IOs for an extra +6 DEF on top of your other Defense. Mu gives you a solid layer of protection against many end-game attacks.
On my Beast/Time I went with Leviathan for theme, but its still a good set with Shark Immobilization cone and Leviathan Armor (S/L/Cold...meh on Cold, but S/L is still good).
You don't really need Elec Fences. You can double Hold runners, as you say, or bosses/annyoing stuff. Elec Fences has a small radius anyway and only the Brute really knocks anything back. So that's a fine approach to go with two holds. Don't forget to put a Lockdown Hold proc into Distortion Field. IT will help stack up on things and is good for freezing minions.
Make sure to go with Musculature when you get your Alpha. Best bet for almost every MM.
Have fun!