The plans are three 128x64 glcd’s at the top (flight data, resources, status), some warning lights, RCS, SAS (with mode selection as well), lights/gear/brakes, a buzzer alarm, throttle, controls for both rotation and traslation via joystick potentiometer, action groups and, hopefully, some kind of launch autopilot (mechjeb style). All was to be done with a Mega, until i discovered the Due (exactly two hours ago :D). If that turns out to be still not enough i’ll try to use a RasPi 3, if it is possible.
Now the box (50x40x15 cm) is done, i still have to do all the wiring and write the program.