Problem is, I don't have the hooks necessary to make standard demihumans seem more non-human.
On the other hand, give me Lizardfolk or Illithid, Thri-Kreen (or Xixchil), and my fellow players will soon be questioning my humanity.
It's something I've noticed in a lot of RPGs-- there's simply no effort made to make the non-human races anything but humans in rubber suits. One of the best games/settings I've seen for this was Alternity/Star*Drive, with all of the roleplaying notes and portrayals of the aliens. (The fiction had a lot to do with this, as well. I need to work on my on-the-fly poetry, but I can finally roleplay a Sesheyan properly.)