Other options exist, but not so polished. It's a tough project that apparently needs more support than small FOSS projects can provide, I've seen a lot of promising alternatives come and go.
Hardware/firmware wise, would really like to see open standards like we have for PC bootloaders. EU requiring nonproprietary bootloaders on phones would be a real step forward.
I used a vertically oriented mouse like that for a while when I had RSI. Also mapped mouse keys to the keyboard with autohotkey, just for variation. These days have a kensington 'expert mouse' trackball and on my laptop its the trackpad like everyone else.