Mars rover wheel with motor and planetary gearbox

Draft version wheel for functional Mars rover model for my friend.
Using his spare motors from CD/DVD mechanics.
Size of some parts is not ideal - was a little modified in slicer (S3D) after first test print (front motor frame and planet gear holder must be sized together). Is missing any cooling holes in motor frame. Top motor for turning is only for decoration - there must be used stepper or servo. Frame for this motor was not printed. Front grey disc is not fully modeled in 3D program, but