After 8 years of being satisfied with Dvorak, I recently began wondering if I should take a deeper dive into Neo. Initially I was intrigued, but then I learned there are so many variants. For many years Neo has been succeeded by Neo 2[0]. On top of that, there's also Bone, and Bone 2, Bone 3, and Flux[1] successors. Also, Noted[2] appears to be the most recent iteration, but it is not official like the others are.
I'm a user of Bepo (French)[1] for many years and I'll never look back to classical azerty and qwerty layouts.
Bepo doesn't split the keyboard per 'usage' per se, but remains extremely fast to use for programming and writing English or German, the German letters are logically set under the corresponding letters in bepo with a modification key.
[0] https://commons.m.wikimedia.org/wiki/File:Neo2_keyboard_layo...
[1] https://web.archive.org/web/20140906202835/http://wiki.neo-l...
[2] https://github.com/dariogoetz/noted-layout
[3] https://github.com/dariogoetz/noted-layout