Hello, Larian!
Let me give my humble opinion.
Mages have a huge number of spells that they can use in battle, respectively, they also have a lot of variations of actions each turn.
But non-casters are limited to very few and uninteresting abilities. I know that you are bound by the rules of the board game, but if you decide to add more active skills to non-casters, I will be very grateful. A variety of abilities is a variety in the gameplay.
You did a great job of making the warriors interesting in Divinity. They had diverse and numerous abilities.
Thank you for reading!
I'm really looking forward to your game.
Really have you played the game much? Non casters have more choices then casters in my view. Casters have a few spell slots that get used up rather quickly and then they are out of mojo. Back to that same cantrip over and over.
Also, I would note, there are different types of "fun". Divinity was "cartoony kids" fun. I do hope that BG3, keeps the more "adult attitude" . Well, I hope it goes more adult with Gore, brutal and dark. That's way more fun then "cartoon" fun.
I personally find Melee more powerful and interesting, but I think that's because we are only up to level 4. I think at higher Levels the casters may start to shine.