It seems like a good idea.
Buying superpowers and supergadgets like grappling hooks, jets, psychic blasts, fireballs, massive punches, etc. Maybe they could all have tiers, and subclasses.
And be only available to certain types of Superheroes and Sidekicks, like Gadgeteers, Psychics, Elementals, Jacks (of all trades) and Strongmen, and they could each have a power or gadget(s) associated with them.
Of course obviously tools and superhero powers could simply be held in the inventory, or "Hero Menu", and be selected Kingdom Hearts style from there.
Feedback? Suggestions for more to add?