That's true, i have one of those "OP" vanguards. Cause most of the time people don't work together much anyways. An asari vanguard lvl 20 with hmm can't recall the exact name, but she has 2 biotic powers that you can keep spamming and auto regenerates your shields, and are super effective.
Also: Why the hell didn't bioware include an ingame chatbox?? It was in the demo multiplayer, why not in the final release! I don't like talking to douches that i don't know with my headset. These kind of things are pretty basic for any multiplayer pc game.