So I've tried the sorcerer and had to restart the game because of an unbalanced party.
In D&D an ideal four-member party consists of two melee strong characters, a healer and a spell caster.
In BG3 if you choose a spell caster or a healer as the main character you end up having difficulties because the companions you get to choose from are mostly spellcasters, other than the rogue.
Solutions to this would work obviously either have your main character as a melee-focused character or perhaps Larian should include an additional fighter to the companions.
An ideal party is different for everyone depending on how they play. You don't need any specific roles, anything will work. Your desired party is 2 melee, a healer and a spellcaster, currently you can do this with Lae'zel, Astarion, Shadowheart and your sorcerer. If you do not like these companions then you can use the trick to make a custom party.
The game is completely possible to play with all sorts of combinations. Personally, if I am going to use a full party I prefer all ranged (two mages, crossbow ranger, and one other which varies depending on mood.)
