Before I crank up the game again as a mage, I'm curious about one thing, and it's been a long time since I last played so I don't have any recollections about the issue. My question is: if you have, say, four members in your party, and you get 10,000 XP for a successfully completed quest, does each of your party members get the whole 10k or just 2,500 XP? The answer to this question will strongly influence my choice of party members.

I like keeping NPCs around for story reasons, because I enjoy their reactions to other NPCs and events I encounter in the game world, but I'll dismiss them behind if they're an experience drain. This goes especially for some of the less useful party members, like Annah and Fall-from-Grace. In Baldur's Gate 2, the XP was distributed among all your current party members equally, and they could miss out on new levels if you left them behind. On the other hand, in SW:KOTOR, all NPCs you could recruit were the same level as you at all times, even if you dismissed them and came back to pick them up much later in the game. Which category is PS:T in? If it follows the rules like in BG2, what is the optimal number of party members to accompany The Nameless One? Also, are there game events in which only certain party members receive experience points (like TNO and Dak'kon when interpreting the Unbroken Circle of Zerthimon, and other NPC-related quests)?

It's BG2-like, XP gets distributed amongst party members. Yes, for some NPCs there are events where they get exclusive XP or where they get straight upgrades (like +1 to DEX/CON/STA). That being said, there's plenty of points in the game and you get even more as a mage with high WIS/INT/CHA because of more choices in dialogue.

In some of the later quests, where you get 300,000+ xp for quests I kicked out my party members just before completing it :D (after which I took them in my party again)

My nameless one was one powerfull mage at the end!

It works like BG2 where XP is evenly distributed, but TNO also gets a percentage bonus on all XP depending on his wisdom. In BG2, the protagonist actually gets a 10% bonus on all XP, too.

I think a party of four works fine, just Morte Annah and Dak'kon. You'll probably want Annah and Dak'kon in your party regardless of other stuff because they can change your class at will, and I like to keep Morte around cause he's funny and has lots of useful dialog. As a mage, you don't even really need Fall-From-Grace because you'll have the Embalming spells for yourself and Morte, Dak'kon can regenerate with a CON tattoo after he's been upgraded, and you've got Blood Bridge for Annah. Plus there's more health items than you ever really need, and FFG is beyond wimpy in a fight.

That said, I didn't have any trouble whatsoever as a mage with a 6-man party, either. Just make sure to switch away from fighter before you get the level 7 specialization bonus. I had no shortage of spells and there wasn't a terribly significant difference in XP level between the 6-man and 4-man parties.

Thanks for answers, everybody! I wondered how wisdom factored into the equation. I guess I'm just greedy for XP. :) I think I'll go with three characters: TNO, Morte and Dak'kon (maybe replaced by Nordom or V'hailor later in the game). My TNO will be a pure mage from soon after I exit the Mortuary. One powerful mage and two fighters, with Morte being the tank due to his resistances, will be just right.

I think you're making unnecessary compromises, but whatever floats your boat. I've played through the game twice as a mage and never had any particular problems. Given that dialogue and story are more important than combat I would rather have a party of six than three.

Fair point. More NPCs = more dialogue, and Torment excelled in dialogue.