Thinking about it, I wonder if it's not another facet of the problem with new characters in modern comics. Most of the major alien races in both universes were created in the sixties or seventies, IIRC, and none of the races created since then have really taken hold in the universe's space culture. The Kree are "Star Trek" blue people, the Skrulls are "Star Trek" forehead aliens, the Khunds are purple pro wrestlers, the Rannians and Thanagarians are basically human...