As I remember, gained experience points distributed among characters. So, playing solo or with 5 companion have different effects on the game. BG is a roleplaying game and not all characters are needed in fight IMO.
I couldn't agree with you more. I've been doing great with my Trisha<Ranger/Knight; Shadowheart<cleric>, Gale<mage>, and Astarion<thief> Since I've learned the gameplay mechanics of the game the party has been able to pretty much handle any situation for which they have run into. Of course, we've not been to the Underdark yet.<LOL> But it seems that 4 is a good number any more than that would just be a pain in the ass.
A pain because control are terrible... Everything is not about combats and difficulty. This is a party management game and 6 companions gives better party management opportunities.
5 is also a better number than 4... 4 is way too limited and works in game that have a very limited number of class/subclasses or suit to players that will play the game way more than once.
This is D&D, not DoS... There are so many classes and many won't have the opportunity to play with less common classes with only 3 companions... Druid, barbarian, monk, bard,... These are usually classes you choose as a 5th or 6th companions if you don't know the game and play a "classic" party composition.
That's exactly why a lot of us love BG1/2. I could always play with the characters I liked (fighter, Ranger/Rogue, Wizard, Cleric/Druids) AND add a little bit variety and/or originality in the team (paladins, druids + cleric, barbarian, more than only 1 caster,...)