twillight: For the firstfew levels you'll definitely have to put the archer on the front line melee.
Monk is not too big of a fighter in BG1, so you'll have to rely on the fighter/cleric and the swashbuckler for a long time to take punishment.
Sounds a bit more challenging than the usualy cookie-cutter setup, but with the right spells (heavy support buffs) and caution it can work out.
I wouldn't worry about the armor thugh. Doing a pure kensai currently proved AC is mostly a legend in BG1. With a party of course you'll need to do a lot of micromanagement (moving out characterfrom harm's way), but that's it.
Btw, you definitely don't need any pure caster, but the cleric/mage, aka. Aerie always slugs behind the party power-wise.
I'm used to be very cautious and micromanage my fights very much (I grew up with Wizardry and Might & Magic, you don't stay alive in those without), so yeah, I know I'll have to pause a lot in fights.
The Monk is more a kite right now, that's for sure; just have to make sure first contact for the enemy is the Swashbuckler or Fighter/Cleric and it usually works out.
Bookwyrm627: The Swashbuckler (basically a F/T that emphasizes the T more than the F) and Monk can help shore up the front line by BG2. The first few levels in BG1 are going to be rough though, with only one (F/C) and a half (C/M) characters able to wear heavy armor; there isn't anyone to fill the gap while the primary tank steps back for a heal, and the C/M loses the M half while wearing armor.
Sarafan: I agree. Monks are quite weak in the early levels. By the time they gain decent fighting capabilities it's already endgame in BG1. In my opinion, if the author of the topic switched one character to a single class arcane caster, the party would do quite fine in BG2. It would be very hard in the beginning of BG1 though.
Bookwyrm627: I hadn't considered higher difficulty levels. I figure the C/M is basically Aerie; the character will do fine with cleric and arcane casting, and the Skald (a bard) should be able to provide arcane casting too, iirc.
Sarafan: I never found Aerie really useful. Cleric should be near the front lines to provide healing and other buffs. To do that he needs a decent protection. Mage is the opposite. He stays behind and takes things down from a distance. These two classes are in a utility conflict. Both are casters, but serve different purposes. Skald is an arcane caster of course, but he's quite weak in this role. He gains access to Breach on level 13, which is very late in my opinion.
Bookwyrm627: Considering you are suggesting two substitutions, which slot would you drop besides the C/M? I'm guessing the archer, bard, or monk.
Sarafan: That's right. It depends on the individual preferences. Considering the fact that ranged weapons are overpowered in BG1, Archer might be a good candidate to stay. That leaves us with Bard or Monk.
twillight: Btw, you definitely don't need any pure caster, but the cleric/mage, aka. Aerie always slugs behind the party power-wise.
Sarafan: In BG1 not, but he'll complicate himself things a lot, if he won't have one in BG2. To be honest, in BG1 you don't need an arcane caster at all. It's easier to have one in the late part of the game (for Haste and Fireball purposes), but it's not a necessity.
Just for clarification, the F/C is for frontline combat and healing, while the C/M is more on buffing/debuffing and ranged support duty. As such I feel they are complementing each other quite nicely, at least for now.
The Skald was my last pick and I wasn't sure what to pick. An Inquisitor, Barbarian or a Dragon Disciple (never played one of these btw, are they pulling their weight?) would have been my other potential picks on that one.
And yes, F/C, Archer and Swashbuckler are totally set. Got pretty lucky with my Archer anyway and rolled an 18/94 on Strength, so no problem employing him on the frontline whenever needed.