Not to abduct a Tigra thread and make it about Stingray (sorry, OP), but it wasn't that long ago the same was often said about Aquaman (Namor got a pass because he's an anti-hero/potential conqueror type). Looking past the fact he can fly and fire laser blasts, I think the thing to do would be to build up his (admittedly fairly undeveloped) personality, to make him unique in that regard. He was a scientist first, then willingly built himself into a superhero for purposes that are long in his rear-view mirror. Maybe he becomes a guy who thinks he's always in over his head but can't bring himself to quit for some reason. That's a dynamic I'd find interesting to read in a character.