Very nice! Maybe look at Synergy for mouse/keyboard/stylus sharing between devices: https://github.com/symless/synergy-core
synergy these days has been replaced for most serious use by barrier, due to the restrictive synergy license and costs.
https://github.com/debauchee/barrier
I actually clicked on this thread for the purpose of commenting that you could do cool things with some combination of this, using spare screen/tablet devices, and Barrier. But you beat me to mentioning the concept.