I’ve been thinking about a magic staff for a wizard. It adds a plus +1 to attack roles and spells saves. It allows you, as an action, to use spells slots to empower other spells. Every level of spell slot will add a D10 to the damage of spells cast the next turn.
A 3rd LV spell slot=3d10 4rth LV spell slot=4d10 5th LV spell slot=5d10
and so on. What do you think?
The power of the wizard spell list lies in their debilitating effects, not so much in damage. Check if something like the Arcane Grimoire might be what you’re looking for.