This is my interpretation of the SimpleBot

Dear Dexter Industries,
I have done a couple of very small improvements when building my own SimpleBot, I have thought you may appreciate seeing those, even if they are minor:

- I have replaced two connector pegs (#2780) at the front with longer ones (#6558) that make the structure even stronger 

- I have replaced the two bushes (#6590) at the back with a cosmetically more appealing tube (#75535) and topped that with a full size bush (#6590) rather than the half size one you used (#32123).

It is not worth merging in your master. Take this just as an homage to the BrickPi team :-)

Giacecco