DIY Control Surface

Hey Everyone! Me and some friends, are in the early stages of designing and building a control surface to work with the major, DAWS and most likely going to use MCU (Mackie Control Universal ) Or Mackie Control. We most likely are leaning towards MCU with its combined abilities. We are all from different backgrounds which, means we have to learn a lot of information about this, more specifically what MIDI data is needed to control specific parameters within the DAW I've backwards mapped it so far that to control the volume you hit (for example) G#6 plays at 127 velocities, THe pitch wheel controls where the volume is (Between 0-127) then G#6 is released I was wondering if anyone has any thoughts on this and/or any information on where I can find more information like this that will help us develop the device further. Cheers