My only concern over this (and other potential new species) is that some missions/storylines/companion conversations rely heavily on a particular species. That is to say, if you're a cathar for example and the mission/conversation you're doing is about cathar (particularly if you're killing cathar), it might be a bit awkward or jarring if there's no dialog mention of your species.
This happens all the time already though. I've killed Rattataki as Rattataki, killed Sith as Sith, and Chiss as Chiss
And of course, humans as human.
It's actually kind of funny when I was on Hoth Republic side as a Chiss and
But anyway, I pretty much expected Cathar to become playable first, and I'm holding off rolling another alt until I can play one.