My current window manager is pretty basic. But that's because I haven't been arsed to script up something, that would help me with window tasks. I tried double monitor for a while, but the main OSs sucked with the way they dealt with more than one. I gave up in the end, so just use a couple of workspaces and window cycle mainly. Main drive is mostly a laptop. Pointer (nub) is too stiff, touchpad is okay - nothing fancy.
Experimental forks would be a safer way to go. I suppose if they don't have massive development teams/effort, it would be difficult to do. It would satisfy everyone who wants to go and invent the future and do exciting new things (which will likely revert to how they should be when real use of them occurs). I imagine the "let's maintain the existing" team would shrink.
Do you use a mouse or touchpad? As resolutions increase, we have to be more precise for UI or just scale everything 200% (like everyone does on 4K screens or Microsoft Surface Pro 4) thereby defeating having a high resolution in the first place......