Nice first try !
Do you have any electronic skills?
For my personnal playing :
I would go for a touch screen, or a simple pc tablet that can be the computer too
I don't use Track Solo while playing, so better to only let track on / off
Buttons seems very big
It is good for comfort at home, but for live, to carry, it is better small and compact

I can add the controllers missing when you will be more advanced in your thoughts