Every boss fight lends itself to certain classes/ranged/casters etc
I can push 600 DPS unbuffed for a full Kara clear as fury, but thats being afk for trash and stuff:
Basics would be something like:
Shade and Maiden should be your bitch:
sorry, but these fights are a warriors dream, constant damage giving you rage and you get healed to boot!
Nightbane and Prince will be your low fights
movement issues that involve being near the boss meaning you die make these fights hard to DPS down
as for a Kara group, most of our healers can two healer it now, but even with 3 coming 450 DPS per person per boss is kinda low, and will make Kara take a while, which is why we should have groups of mix geared people going to Kara so we can get two clears in roughly the same time.