I hope everyone that advocates for an increased party size also understands the implications on basically every single aspect of the entire game regarding balance.
This would in-effect basically cake-walk significant majority, if not the entire game.
Go play DOS2 with the standard 4 characters on the hardest difficulty (Tactician) then get a mod that adds only even ONE extra character and realise how trivial the game instantly becomes.
There's something to be said for challenge and less-is-more. If they've made/making the game around a party of 4, something like two extra characters, on top of being hugely imbalanced to the entire game, also becomes a massive micro-management of the party. Not to mention the various compounded-effects on the dialogue and story.
Going from 4 to 6 is where you get to that point when you keep folding a paper to the point you can't fold it any more. I honestly just cannot see this happening. As much as people want this to be DND, it's just not.
The game is actually called Baldur's Gate instead of Divinity Original Sin so yeah IT IS D&D and that's how they should focus it. About challenges of course right now on low levels there aren't many hard encounters (even the goblin part is ok) but do remember unlike any game made by them D&D has a lot of monters, a LOT to choose and design encounters. With some very epic and legendary ones specially on the late game, ones that actually need you to have a variety of characters like bard to support using Countercharm or Hypnotic Pattern, or a Paladin with their auras, A Wizard to cast powerfull spells and control, as well as a Cleric to Control/Damage/Heal and of course a Rougue to Search for traps/disarm and lockpick, and should I mention a Barbarian or Fighter as well to Wreck Havoc at the enemy lines, and a Ranger to shooting things down and dealing tons of damage?
Stop thinking like DOS cause it might be Larian but it ain't DOS. This is D&D and every class brings something to the table and being restricted to 4 is actually damaging in the aspect of supporting each other in the mid and late game.