Feal Thas

My party is driven by my Pc's alignment.

In BGI, if good:

PC, Imoen, Minsc, Dynaheir, Ajantis, Branwen (if my PC is a thief type, I drop Imoen and add Kivan, if a Paladin, I drop Ajantis and add Yeslick, if a Ranger, I drop Minsc and add Xan and if a Cleric, I drop Branwen and add Kivan)

if neutral:

PC, Imoen, Jaheira, Khalid, Xan, Branwen (I sometimes take Garrick, depending on my PC class)

if evil:

PC, Monteron, Xzar, Viconia, Shar-Teel, Edwin (if my PC is a mage type, I drop either Xzar or Edwin and add Kagain - if a thief type, same with Monteron - if a Cleric type, same with Viconia).

In BGII, if good:

PC, Anomen, Minsc, Keldorn, Jan, Nalia (that is basically it - though I sometimes modify it a little based on my PC class and switch one of the others for Arie, Valygar or Mazzy)

if neutral:

PC, Jaheira, Jan, Nalia, Anomen, Haer'Dalis (sometimes I swap Valygar in, depnding on my PC class)

if evil:

PC, Korgan, Jan, Edwin, Viconia, Anomen

So in BGII, I never take Yoshimo and almost never pick Imoen back up and almost always take both Jan and Anomen. Jan is a very good thief and is a good secondary mage and Anomen is simply the best cleric in the game (due to his combat abilities combined with his clerical spells).