I've just finished BG and imported my char, a Bard turned Skald. This is the team I'm planning to get
Viconia
Korgan
Imoen (Jan Jansen for the first part of the game)
Minsc
rotating 6th spot

Do you think I gave everything covered? I've never played beyond chapter 4 (IIRC) before so I don't know what to expect later on :)

You've got both divine and arcane spellcasters, a thief and tanks... Looks good to me :)

I'd probably skip Minsc and go with Edwin, but I'm a real fan of arcane magic in BG2. Imoen will have less experience than the rest of the party. I'd recommend going to Spellhold as early as possible to even out the experience diffrence.

You might run into trouble later on with low level casters, since SoA is a casters game imo. Your bard will only get lvl 6 spells, and with Imoen behind, things could get rough, hence I recommend picking up Edwin instead of Minsc or just fill the sixth slot.

Everytime I pick up Imoen, I go to Spellhold as early as possible. All the quests can be done afterwards anyways and I find Imoen more or less useless if you've completed most quests before you pick her up.

That party will perform as well as any. The bard stronghold is fun. The Skald is a reasonable kit, but the HLA enhanced bard song will make the advantages obsolete.

Any particular reason why you've never gone beyond chapter 4? What alignment are you? How do you like to play?

I only had one game that went beyond the begginings and then I've realized that I don't really like my PC ;)
My aligment is LN, so I would rather like to avoid to many evil NPCies. Viconia is there for the romance, and I can't really think of a non-evil tank to replace Korgan.

Keldorn? He's a boring old racist, but gets to use a certain +5 weapon and fullplate.

It is difficult to replace Korgan -- he is a very effective tank. However, I view roleplaying as more important than powergaming so I only take him with an evil PC.

You might think of using Jaheira. With a good girdle and the spell ironskins she can tank with the best of them. She also has a good romance (but I like Viconia's better). As a druid, she can cast very good anti-mage spells (insect swarm, insect plague, and creeping doom) and conjure fire elemental is great spell.

Valygar is often overlooked. He can dual wield katanas. Keldorn is also quite powerful and a very effective mage killer. The only problem with both of these is they could end up fighting (and killing) Viconia -- it doesn't happen every game and you can reload to a previous save to get by it. I also never keep Keldorn after doing his quest.

One item to note in the game: An NPC's level is based on your level when you first talk to them. As a suggestion, go do the unseeing eye with Keldorn and the Planer Sphere with Valygar before talking to Korgan -- see if they are 'good enough' for your playing style. If not, grab Korgan at the higher level.

As a group:

PC Skald
Viconia
Jaheira
Minsc
Jan Jansen/Imoen
Valygar/Keldorn

... is a very powerful group. You can then drop Valygar/Keldorn to pick up Sarevoc in ToB if you wish. The ability to shift both Sarevok and Viconia away from evil is a great plot line in the saga.