I assume effects gained by racial overrides are intrinsic, so should be available without a spellbook. That's specially obvious with the Lycanthropy "spell" you can't even access thru magic.
I think it could be fixed by:
- allowing access to spellbook window if you have a spellbook or your spells contain tagged spells;
- you have access to untagged spells if you have a spellbook and always have access to tagged spells.
Looks like the simplest solution, handles racial overrides that don't give you extra spells, and should be compatible with modded tagged spells.