I'm up for anything that will balance him. I'm not sure on how you see your character, but I've always seen this race as more focused on the psionic side, so I'd gimp a bit his physical abilities and have better psionic skills. Maybe taking control over a deficient body during it's ceremorphosis?

I'm obviously not going to dictate which should be your take on your character, I'm just stating what would be my take.

Anyway, as long as you are not way above the average power level of the group, I'm fine with whatever.

EDIT: Answering your question: yes, that would probably work. Just try to not murder the concept you have of your own character.