Did you consider using sway[1] as your window manager? From what I understand wayland is better equipped to deal with modern displays and touchscreens. (although it is still more complex to do certain tasks like screensharing).
Thanks for this suggestion, to be really honest: I simply didn't know about Sway.
At this moment I am experimenting with using the tablet with a Surface Dock, connecting it to different external displays. The way Sway can handle different scale/DPI's per display seems very useful. I will absolutely give it a try!
willemlaurentz|5 years ago