I'd stick to feral / ret. boomkin / ret requires manabreaks, which is annoying.

Imo you don't need a seperate spec for kitty or bear. At 80 i even dps, tank and pvp with 1 feral spec. I think you can let the ret tank pretty well and kill stuff with the druid shredding. Maybe, if you can do a lot of bigger pulls, you can tank with the bear, swipe + do consecration on the ret. I guess that's a good setup aswell.