The Stalker Martial Art powers are quite possibly the least damaging attack set of any combat class, in CoV or CoH. It's very fast, and has some cool crowd control like Spriggity said, but I think a lot of my distaste with the Stalker was due to picking such a non-lethal powerset. Her character concept would fit nicely with a Brute using Dark Melee (a creepy set with lots of clouds of energy and whatnot) or a Stalker using Ninja Blade (though that's not really a superpower either). Technically, Fragment does have super-enhanced reflexes, but those aren't as cool as big flashy attack powers.
Speaking of Brutes, I played Never for a while last night in a group, and she really cleaned up. We had another brute for a while, on a 5-man team, and we went through stuff quickly but I never built up any appreciable Fury. When that Brute left, along with one other, and we were down to three I was able to build up quite a bit, so I thought it was just group size, but we ended up back at 5 people and I was still able to get a lot of Fury in a protracted fight, so I think the big difference is the presence of another Brute. If there are two melee classes fighting each other for targets, you don't get much Fury, but if you're the only one it's much easier. Incidentally, the group had the dumbest Corruptor in the world--he would start every fight by firing off his biggest aoe attack, usually before we were ready, and then we'd all have to save him. He died three times, to no one's surprise.