This could be all wrong, and perhaps you guys already know about this and I am just wasting my typing skills here.
Momo means Peach in japanese, but not only that, Pink in japanese is Momoiro (literally Peach Colored)... yeah you got it, Momo has pink hair.
But the thing doesn't end here... I think there might be another reason why Momo is called Momo, and I started thinking about it now that a chassis line appears and is called idoru, or just idol. The new chassis still has pink hair (seems to confirm my idea that the Momoiro thing is correct) but the whole Idoru mention made me remember, there is an idol that has a very similar name, Momoko (literally Peach girl), that actually also goes by the shortname Momo (
http://en.wikipedia.org/wiki/Tsugunaga_Momoko).
Could the character Momo be in fact homage from the author to the idol Momo.