One thing that has always bugged me is that you can technically wield another gauntlet in the slot, but cannot use the spells - maybe some addition of dual-wielding would make it look cooler?

It can be pretty much OP, but probably with some tweaks like decreasing the damage or effectiveness on each hand would do the trick.
I think two different gloves can have different focus select wheels, so you can drag your mouse from one to another to select a different type of focus.

Also maybe some synergies can help - like casting some spells will combine their effects and turn into a whole new different kind of debuff/buff.

The dual-wield feature can be restricted to Void gauntlets, because of high Vis consumption.

Sorry if it is out of your scope.