See it's too constraining though. Like, that's literally going to be everyone's party to a T. In Divinity you could mix up classes a lot easier, but this, it's D&D, it's Baldurs Gate, and it needs to be different.
You don't want to take forever to heal or not be able to remove curse / level drain / poison, so you need that cleric. If you don't have a hefty front line fighter you're going to have a bad time. No rogue means eat trap city and no lock picking doors or chest for you which is absurdly dreadful and no one would pick that so literally every party will have a rogue, and similarly to the other 3 no one wants to miss out on having at least some of the vast library of powerful and useful wizard spells and some good AOE for the tougher battles, that is when the wizard/sorc shines. If you had a 6 character party you basically have two slots you can add in some real spice and change up your party. 4 characters is 100% predictable and pretty much may as well be locked in imo.