I add my personal points:
7. Incantations for wizard spell!!!!!! Not just click and KABOOM FIRE EFFECT!
I like all of your suggestions.
Only incantations will prolongate spell casting a lot. Combat feels slow. Incantations will make it even longer.
My observation is to make combat snappy and faster.
Irenicus dungeon has about 15 encounters. Those encounters in BG3 would last too long.
