I hope that I am at the right place here 
At the beginning I was very enthusiastic about Ubuntu-Mate. Hower, after finding that MATHEMATICA and Python RPi.GPIO cannot be used under Ubuntu-Mate I am a bit disappointed.
Do you plan to solve these problems? At least the GPIO problem seems to be fixable by setting appropiate parameters in the kernel and recompile it. Concerning Mathematica you certainly need some goodwill from Wolfram 
A short answer would be very much appreciated! Thank you.