Digitizer issues are usually from getting the wrong digitizer. They are programmed differently for the HAC-001(-01) (v2 classic switch) vs the HAC-001 (v1 classic switch).
More specifically the game card reader board that the digitizer plugs into needs to match. So make sure you buy your digitizer to match the game card reader version, or buy a game card reader to go with it (you can get them for ~$14). Unfortunately many digitizer sellers on eBay don’t say which model it is designed for.
Alternatively you can mix and match those versions if you have an unpatched/modded switch. Just launch Hekate, go to tools and run the digitizer calibration.
I haven’t repaired too many switches but the first time it happened to me I had a spare v2 game card reader and that fixed it immediately. Second time I used the Hekate method and that worked just as well
One nice thing about KDE compared to most of the other DEs is that the window manager (kwin) is separate from the underlying components, and it can be replaced!
There are many walkthroughs like this one out there: https://github.com/heckelson/i3-and-kde-plasma
You get i3 for tiling window management but you still get to use KDE’s system settings to do configuration like display settings, themes keyboard shortcuts, etc, just like you did before. You can also pick and choose which parts of the KDE desktop you want to keep (menu, krunner, etc)
Since i3 is just a window manager and is lacking all of that system level stuff it really rounds out i3 to feel like a full DE instead of having to piece together other tools to do those things.