Role-playing wise, hmmmm, You are a Paladin, so you would keep the other paladin. Imoen is who she is (if you've rescued her, you know what I'm saying here) and you wouldn't drop her, and Aerie is your lover ... leaves Jaheria and Minsc. With only Aeria as a half cleric and the two paladin's healing to back it up, I would kick Minsc to the curb, his fun roleplaying quotes and all. Jaheria is too valuable to the stability of the party, and Jan will give you another reserve magic user to play with. Two tanks, a Druid, half a cleric, three halves of mages, and two halfs of thiefs makes for a well rounded party.
BK