Give some Wizard Spells Drain (Damage that requires rest)

[Bombadil]

If you want to try and balance spells without making massive cooldowns this is one way

Drain: Is a form of damage taken by spellcasters when using their abilities channeling magic is difficult and can lead from (disabler like damage) to Physical damage. Neither of these can be cured via healing one must actually rest.

Not all spells should have drain but its an idea to limit mass ei nathing magic missiling