@brock, MIDI note entry is a great idea.
TBH, as a far as I’m concerned, entering the custom scales can be an H90 Control only option.

I actually remember that MIDI toggling post of yours from back in the day! very creative. but I want something simple, with a set-and-forget approach.

I recall when the H9000 came out, a lot of users were asking for custom scales, and it wasn’t added for years. I’m not sure if they ended up adding that?
I think I read somewhere that it was more complicated than it looked (something to do with the new device architecture maybe?), but I might be wrong.