You guys are forgetting the reason why the species in the game are very human like, and its not that bioware is lazy. The playable species in game as mentioned by Daniel Erickson and other developers is that a character has to be romanceble. In other words walking carpets, fish faces, and alien monstrosities won't work as playable species. Plus you won't find a jawa so adorable if you see whats under the hood. Another thing is that most species should be mammalian so they can possess the human body type. That being said I think that Togruta, Arkanian, and Cathar would fit well in the Republic. While Chagrian, Zeltron, Zygerian would not be bad in the Empire. Also Nautulan, Kiffar, Duros, Nikto, Devaronian, Elomin, Bolosar, and Iktotchi are plausible. The only problem being to add enough variety in their customization and managing head slot equipment such as helmets and hoods.