I've been using KDE Plasma Wayland (never tried X11, I really need Wayland) for almost a year. There's always tons of small bugs and even some big ones. Each big update they shuffle around and you get another headache. I'm talking in general, I also have Kubuntu+Wayland in another computer. On Kubuntu 18.04 I was getting constant segfaults and losing the entire session. Both intel and amd. That bug was "fixed" but not really and the full pc freeze became just a logout. The .config files are a complete mess, even opening and closing a program like Dolphin makes the state change. It's insane.
Am I really unlucky or are you having the same experience?
ps: I would use Sway if I could have a sane floating window experience. Just a maximize and close button. And alt+tab. 80% of the time I'm using my mouse, I'm no vim wizard. Even mpv runs smoothly there. KDE is getting on my nerves.