I do Tatooine, than Manaan, Kashyyyk, and last Korriban. Tatooine first cause I like HK and Calo is at his easiest there, Manaan cause I typically do the bounty hunter's guild with the long weird names missions, then Kashyyyk, and lastly Korriban so I can have my jedi entourage without Bastilla.
Although sometimes I switch Manaan and Kashyyyk cause I feel like it. And sometimes I just go to Tatooine long enough to get HK than, I leave. It all depends on my mood though....