So, I'm an old school gamer and I usually just let things pan out. HOWEVER... This is a special game to me, being a Baldurs Gate, which is one of my favorite games of all time, as are all of the good old D&D computer games. And in nearly every one of those games from the old DOS TSR games to the original Baldurs Gate I & II, Icewind Dale I & II, Neverwinter etc etc. Almost every one of those games had... A SIX CHARACTER PARTY.
Now, maybe I've missed something, and they (Larian) already plan on doing a six character party, but it really sounds like they are shooting for only 4. And I understand doing that with multiplayer is different, and if 4 players is the max actual players for multi but still have a 6 char party, that's fine (1 or 2 players could control multiple chars in multiplayer). But if we are limited to a 4 person party throughout the game (not counting little minions etc, like actual "player/party" characters, I'm doing to be very disappointed honestly.
I know you guys will make a great game and I absolutely loved DOS II, wonderful and amazing game, and I kind of assumed that BG III may well end up looking very, very similar. And it does, and that's fine that your mechanics and such look similar and the world is different (and more polished). But, without a 6 character party, it's almost like I'm going to be playing the next Divinity, in the D&D world, not so much, BG III if you understand what I mean. All the other games I fondly remember were the 2D isometric view that is totally iconic at this point, and all of those games had a 6 character party. Maybe it would have been cool to do some interesting adaptation of the perspective of the old games like BG I & II and the pause but I'm sure that playing turn based will be just fine. So, I'm ok with the very different flow of the game from the original's real time pause to something more of an improved DOS II world & battle system, but I'm not ok with a 4 person party... Just not at all.
Please, please, please, make the game with a six person party. I should have piped up immediately when the game was announced probably but, I figured I'd watch and see where it goes, and hoped, that 6 person party was just kind of a given. I was concerned since DOS II was only 4, but I hoped you'd all say, well, every other BG & similar games were six character, so we HAVE to do six! AND I WOULD HAVE AGREED! Haha.
I hope others will agree and if this hasn't been brought up by players yet, I don't know how it could have possibly been over looked since that was such a big part of not only the first two Baldurs Gate games but nearly every other good D&D computer game. Maybe the devs won't like me bringing up this idea really at this relatively late stage, but, I hope that we can all see what grander scale 6 characters brings to the table...
Fortunately D&D 5e eliminates the rigid roles of old school 2nd Edition AD&D so your six character party isn't necessary.
Every character can spend Hit Dice to heal themselves at a short rest. Every character can stabilize a fallen comrade. Clerics, Rangers, Bards, Druids, Paladins all have access to healing spells. Fighters can heal themselves with second wind. It is also my experience playing and DMing D&D 5E that healing spells are very inefficient (they don't scale well) and the absolute best way to "heal" is through crowd control and damage (Kill them before they damage you).
You don't need a rogue if you want a stealthy character. If you choose the Urchin background your Warlock, Cleric, Wizard or Fighter can be proficient in Sleight of Hand, Stealth, Thieves' Tools and Disguise KIt.
You can make a Githyanki Abjuration Wizard (will be my first EA character) who wears Chain armor, wields a Great-sword who psionic jumps into the front line.
D&D 5E is a much more flexible system than old school D&D giving you the flexibility to create an effective and balanced adventuring group with a smaller number of characters.