I’m using a MacBook Pro as my portable rig, and I can’t see it working well on that resolution - I really need pretty much the full screen for any of the windows I’m working on. As for the main rig, that’s 4x monitors - I don’t think I’d find a permanent split useful on any of those either really.
I think any improvement on floating windows would have to be dynamic in some way shape or form, something that expands when in use and retracts when not.