You might be interested in the Hexboard. Basically a mini-lumatone for ~$500; main downside is no velocity sensitivity.

https://shapingthesilence.com/tech/hexboard-midi-controller/

I'm quite happy with mine, and play it with the Wicki-Hayden layout.

https://en.wikipedia.org/wiki/Wicki%E2%80%93Hayden_note_layo...