The new munchkin race of choice is . . .

[Bran Blackbyrd]

I'm not really worried about non-standard races being overpowered. I don't think any of my players would even think of playing as one, and if they did it would probably be a planetouched.
The only guy in the group that would be prone to min-maxing isn't familiar enough with the rules to try. At the end of the day, none of them would pick a monster race anyway.