Hallo!
As far as steppers go it would be nice to have arduino commands for steppers. It looks like the existing pduino firmware code can only change one pin at a time, it would be nice to have a parallel digital pin command with a mask like set_digital_outs(int output_pattern, int mask) so the set bits in mask would be changed, at the same time, according to output_pattern and the zero bits would be unaffected.
AFAIR it is like this - only that the output bits are splitted in 2 halfs (7 lower and 7 higher bits) ...
LG Georg