Regarding player character races/species in tabletop role-playing games: Why play something other than a human if not for any advantage in game mechanics? In my opinion, that’s the only reason to play something that’s not a human (unless you have a game with no humans).
Some might mention the role-playing aspect of it all. But if you think about it, the vast majority of players run their characters exactly the same way regardless of race. You might play the snobby elf, or the rough & tumble dwarf, but those behavior are driven by the implicit character’s culture, and are not derived directly from their race or species.
In addition to that, those role-playing behaviors are not alien to a human character. Your human can be as snobby as any elf, or as feisty as any halfling.
There’s been a lot of people proposing lately that all race-related bonuses should be removed from role-playing systems, and that all bonuses must come from culture-based influences. An orc shouldn’t be inherently stronger, or a halfling shouldn’t be inherently more agile. But if we remove those advantages, then what’s the point of having playable fantasy races and species? Just to be able to say your character has pointy ears or blue skin? It loses all meaning. You’d need to create some cultural tweak so extremely alien to what a human would do that it might be just unplayable or simply unattractive.
If you’re removing all advantages from having different races, then there’s no point in offering them in your game. It makes absolutely no difference, and I suppose you could have player characters either be a single race or species, or the totally opposite direction and allow player characters to be anything: an owlbear, a human, a dog… basically, anything that’s alive.
I’m not stating that one approach is necessarily better than the other; this is determined by the kind of world you’re creating for your system. Just keep in mind that the more options there are, the more things you need to keep tabs of to maintain game design balance, especially if your system is rather detailed and elaborate.
Let me know what you think about this!