Sliding back on topic...
I suggest you take Edwin and Korgan, at least. They are the best powergaming mage and tank, respectively. They also have two strange quests that are worth playing at least once.
Also take CN Anomen for a cleric and a romance. There isn't much different between LG and CN Ano--I think it's just a 2nd level spell. Whee. Korgan and Anomen will provide all the pounding power, and Edwin's extensive spell knowledge comes in handy. Jan is also a nice addition to the party, being a thief and all.
I suggest you take the Skald kit. You don't need to be a Blade--you've got strong fighters to whack things. Play a skald, go with missile weapons, and sing. Your bard song will help your fighters immensely.
If you have five slots filled, you can always pick NPCs up for their dialogues. If you go with PC/Edwin/Korgan/Anomen/Jan, try picking up Aerie, Mazzy, Valygar, or Jaheira for some interesting results.
I don't suggest Haer'Dalis because he's not as fun with an evil party as he is with a good party. I think he'd work well in a PC thief/Jaheira/Nalia/Aerie/Keldorn party.