As stated, level 11 through 13 is the most likely range, allowing for a peak at level 6/7 spells and similar upper mid level melee attacks and skills, and at least two huge leaps in character mechanics. Once you get past that, you are working with high end characters approaching, if not at, epic levels.
That would require another quantum leap in development, programming, imaging and writing - while foreclosing any meaningful sequel.
If you are looking for a D & D game with that range - level 1 through 14 - 20, Pathfinder is your best bet. It will be an awesome game, but less demanding in terms of cut scenes, and other areas higher in developmental costs/requirements.
I'm looking forward to the different RP experiences that will be available between Solasta, Pathfinder and BG3 - along with a few other such games coming out in the next couple of years.
This is looking to be a banner period of Fantasy RPG's.
