I just hope the UI gets a bit of an overhaul so other abilities are kept out of “spellbooks” and wizards are the only class that use spellbooks
100% agreed. Right now that entire section of the Character Sheet is labelled "Spellbook", even if you're a Battlemaster Fighter and cannot cast a single spell.
To your point, Clerics, Sorcerers, Bards, etc wouldn't have a spellbook either, despite being full spellcasters.
Non-casters shouldn't have a Spell Attack/DC section displayed at all (they currently do). The game uses these stats (defaulted to INT) right now to calculate for casting via item, which is also a balance issue. In Table Top an spell casted via an item has its own DC, which the game doesn't have right now.
