Just for the sake of trying new things, I tested out the T-Sent build in the OP with minor variations:
-Tech Armor 4a instead of 4b. The 5 percent DR is alright, but I really dig the stagger explosion having a bigger radius. That makes a huge difference when I have to rush into a mess of mooks to revive somebody.
-No LOLcolyte. Because.
-Barrage Upgrade, no Geth Scanner. Just for RP purposes. That and my Lancer is at VI, not X, so the ammo capacity helps out a lot.
-Passives on 4b, 5a, 6b due to the gun being heavier. Might switch to 4b, 5b, 6b.
All in all, I really enjoy this setup. It is superb on Platinum. Being able to cast powers and shoot and never have to run to the ammo box gives him loads of utility. Previously I ran a 6/5/6/4/5 build, but the passives make a profound difference. Non-boss enemies drop like flies. Bosses like Atlases and Banshees don't last long because their armor means nothing. He can even kill on-host Phantoms pretty quickly. And I believe that going into rank 5 Fitness with him is absolutely worth it, even at the cost of tech armor power damage or maxing Warp. Faster shield regen = less time behind cover. Less time behind cover = more time shooting. More time shooting = more headshots.