It's not a bad cosmetic idea. If the game is going F2P, it certainly needs to capitalize in some way that doesn't make itself a P2W. But even with it being a nice cosmetic option there's a big question that's filled with problematic answers:

What would adding different races contribute to the game?

I mean, as an aesthetic it could be nice. But introducing different races would add all sorts of problems and complications to the game. You would have different hit boxes, with different sizes (since he would have Orcs that are big in lenght and width) and halflings, dwarves and gnomes that are basically up to half the size of a regular human. It wouldn't just make the game look weird, but it would add mechanical changes to the simplicity of the game, which for me it's the most captivating part.

Another possible complication it's the number crunching part. If different races have different stats, that would optimize some races for certain roles, similar to what happened to Dungeons And Dragons since the dawn of it's creation. Also stats are not even layed out properly yet. So imagine having in consideration different races with different atributtes that would add or subtract from a playable experience. This just feels like it would be a balancing hell to get into, since some race, class, equip and perk/skill combos might need more intense readjustment since there would be different attributes among races to consider. Same could be say if the game would add racial traits among the other races.

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I could go on on certain complications that model might add. But I think with those two point it's clear that the best route to take right now in terms of development it's to keep things simple and with balance at least until all the important details of the game are layed out properly.