I haven't done Kara since 70, but towards the end of T5, you could 7 man it with a single tank.
Netherspite might be hard for a group, because of needing to dance the beams.
I'm not sure how bad the lava areas are for Nightbane.

As for the trash up towards Moroes, it should be a lot easier now with the AoE changes.
Moroes has the four adds once his room is clear. I'd imagine you'd kill the adds in sequence first, in order of whichever is most dangerous.
If you outgear it enough, and with 80's that might very well be the case, just have the tank AoE everything and burn Moroes down with AoE gradually getting the rest.