My biggest disappointment in the rules is the same ones I've had for the last few years. I feel that the pneumatic rules are too restrictive (only allowing, basically, whats in the KoP).
I believe that they remove a lot of creativity with pneumatics by not allowing teams to use things like Electronic pressure controllers, cylinders with feedback potentiometers, pneumatic actuators (other than the one allowed), Different pneumatic compressors, valves with different CVs and pneumatic motors.
I believe that, instead of only allowing specific cylinders and such, they should require teams to prove that their pneumatic system is safe by showing specification sheets for their pneumatic devices. I also believe that instead of telling teams they can only use 4 clippard volumes, they should limit the volume of the entire system (this is easily checked by putting a known volume of air into a system and looking at the pressure).
The kids (and most of us mentors

) are pretty smart. As such, instead of limiting their options, we should require them to prove that their (pneumatic) designs are safe. Lets see what wild ideas they come up with.
JMHO