...I've actually never used MIDI.
Basically what you've got is a "input hardware test" program. If that's working, great.
Do you have a "traditional" serial MIDI connection with the round connector, or are you using USB-MIDI?
Next, I'd suggest you figure-out how to send just one or two MIDI commands (with no pots, switches or any input) before you try integrating all of that hardware.
Then if you want to program a switch to send note-on and note-off commands or if you want to [u]map()[/u] the default 0-1023 pot reading to a 0-127 MIDI velocity, etc., that should be easy enough. But, I'd recommend that you work on one control/message at a time/