I want the spell menu from NWN2
You can open or close it if you want.
You can see all spell you know sorted by level.
You can cast any spell at any level (used to be highten meta magic for sorcerers in NWN2, in 5E it would be like this for everyone).
Adding a recast button to the menu should not be a problem.
There could be a similar menu for class abilities.
Pathfinder kingmaker is a good start, where you have 3 menues to open ( spells, special abilities, usable items.)
The UI could be improved and the spell menu from NWN2 was better, but it is a start.
Putting everything in hotbars only gets confusing fast.

Prof. Dr. Dr. Mad S. Tist

World leading expert of artificial stupidity.
Because there are too many people who work on artificial intelligence already