[elihu]

I also have a software background and have been learning hardware design recently for a midi controller project of my own.

For the project you describe, you probably don't need more than a basic understanding of electricity. You'll want a microcontroller. I like the Teensy, as it has good libraries and many people have used it for midi-related projects.

You'll probably also want to design a proper PCB. You wouldn't have to, but once you know how to do it, it opens up a lot of possibilities. Kicad is great, once you get the hang of it. The learning curve is steep. There are a lot of good videos on youtube though.

I've been using JLCPCB for boards, and mostly Tayda for through-hole parts. JLCPCB's minimum order is five boards, and if you aren't doing anything fancy it's usually super cheap.

Boards can be either be all through-hole or you could have some surface mount. Surface mount is great for mass production, as you can order the boards with the surface mount components already placed, and it's cheap.