Im fine with makeb, but since we paid for an expansion, I think they should have thrown in a second planet just to make everyone happy, one new planet, one old planet.
My vote goes for naboo. There would be no need for a storyline on naboo, it could simply be used for farming credits, simply the more gungams you kill, the more credits you get. World boss would of course be jar jar, even though he doesnt exist yet, id be okay with it. All members of the ops group would be required (for their own sanity) to use a device that leaves him unable to speak. Upon defeating him, all members of the group would earn the title, savior of the galaxy.