If you ask me, I think all races should be comparable in terms of ability. I mean, fantasy games have popularized the notion that humans are the "jack-of-all trades," elves are immortal and "perfect," orcs are strong, dumb fighters and dwarves are the advanced techno-miners, etc. 

This leads to pretty boring rehashes over and over, even in new material. For some reason, people are afraid of breaking the standard tropes and trying out something new. So I'd recommend to do away with these common themes and differentiate among them in different ways - cultural norms, art, architecture, religion, etc. can give flavor to these races without limiting them to certain long-established traits. 

Not to mention, humans have tons of diversity - we come in all shapes and sizes, and individuals have different strengths and weaknesses. Why don't these other fantasy races follow the same natural trend? Not every orc is going to be a musclebound powerhouse, not every elf is going to be tall and graceful, not every dwarf need be an astute mechanic. They should exhibit levels of diversity comparable to humans.