You have a very interesting project going. I envy your skills in electronics. As for me, with no such skills, I have been looking for a powerful and large touch screen otebook. My 10 Suface Pro is too small, my Lenovo Yoga could be a little bigger than its 13.3 inch screen. Still, I can do a lot of things on it without glasses on. In fact, among all the music software in my Lenovo Yoga, vArranger is the most usable music software. I can access so many functions and call up sounds by easily touching the screen. Besides, bluetooth keyboard, wireless gamepad, and other midi controllers such as the Korg Kontrol2 all programmed for vArranger give me a lot of functions on the fly. I can see that when I travel overseas, I won't even have to have my midi accordion or keyboard. I can use anybody's keyboard controller because all the control functions are programmed in the other devices. Anyway, I bought a 15.6 inch touch screen tablet notebook 16GB Ram and 2TB SSD only to find out that it came with 8MB RAM and 1TB SSD. I returned for a refund. Since vArranger is software, it is nice that you can be very flexible with it; either go for a system like you are building or just take your laptop with a small midi control surface.
"You Shall Know the Truth, and the Truth will set you free."