Hi,
I suggest adding 2 kind of weapons that can be use in the character main-hand, but recharging willpower.

• Wand: Main-hand spellcasting focus. Range attack.

• Scepter: Main-hand spellcasting focus. Melee attack.

That way, we would be able to create a spell caster that uses shields in their off-hand.

I know its a lot of work, but I think it would pay off in the long term.

Have a nice day !