Repaint scheduling
Right now we're not doing a very good job at minimizing input latency. However, wlroots & sway are seeing some progress there which we could easily piggy-back on and/or develop further.
https://www.collabora.com/about-us/blog/2015/02/12/weston-repaint-scheduling/
https://github.com/swaywm/wlroots/issues/655