What teams do I use for Heroic Rancor and HAAT?

The Rancor is fairly easy. You need a source of tenacity down, because the Rancor has insane amounts. You also need a source of TM reduction. CLS + Raid Han are an example for a couple of toons who can do it by themselves. Other than that, everything else is a bonus: damage, TM gain, speed down, potency up for your team... They can all speed up the process, but they're not necessary.

For HAAT, each phase has a different mechanic to beat. Follow the advice above and you'll do fine.