You know what, i just drop my personal list of noteworthy shell-tools here (note directfb2 and twin). And edir, clipboard, pass and portal/croc for the win.
I believe XWayland does, in fact, use X. That's the way the compatibility layer works - anything that isn't wayland-native gets ran in an X server, and XWayland then handles the input and display between Wayland and the internal X server.
Oh, interesting. I should really try it out. But I've been on the "my machine's working, and there's no real incentive to change thing" team for a while now :D
Yeah, the reasons to switch to Wayland are either just to use the newest thing, or niche things like fractional DPI scaling support in GNOME. I started using it for that and decided to stick with it, even though I no longer need that, and so far it's been fine.
Many people complain about Wayland being a waste of time because of the missing features - I hope it grows to be a full fledged replacement of X, it's probably not something you should be explicitly switching to if you don't want to deal with the issues. I like setting things up and learning how stuff works, so it worked out for me.
I can tell you that if you switch, for example, screen sharing will probably be broken in various applications, you might experience some issued with copy/pasting between applications, screenshotting/screen recording software might have issues (in particular, there's no way for an app to know where its window is on the screen), at least on Plasma some apps/games will pause/stop working when minimized, because they stop rendering and they might have logic tied to that.
So... Yeah, might be fun to try out - you can have both installed at once and choose which you want on the greeter - but might not be good enough as a daily driver for you.