I think this is probably just an EA issue? Agreed though, I was definitely a bit sad when I realized that Humans, Elves, Half-Elves, and tieflings all share the same body model. Isn't that probably just because the bodies are lower development priority at this point though?
Also, the female Githyanki is just the generic female model as well I believe.
Elves should DEFINITELY get their own body model at the very least, and yeah, the heads and facial hair feel way too human.
Yes, even the tieflings were a more varied bunch back during 2e; all one needs to do is to skim through the various Planescape supplements and they'll see this to be true.