I have a little idea for your mod. Do you remember Xor, the twi'lek who wanted to enslave Juhani? If you do, you must also remember that he hates aliens. Now, why would he hate aliens if he himself is an alien?
I saw on Wookiepedia sometime ago that in the Xbox version of KotOR, Xor is a human, which makes a lot more sense.
How about changing Xor's head to that of a human?