A yes or no would be cool. I understated a bit on why I love working this way, and it is interesting that that isn't important to the several enthusiastic advocates here. Noted.
Sorry, I only recently started contributing and don't really have an answer to your question. I'd venture to say there aren't that many lem devs/"enthusiasts" browsing this thread so I can only speak from my own limited experience. You're free to open an issue to get better feedback though.
Also, I'm having trouble visualizing the workflow you mentioned with overlapping frames, do you have a clip/screenshot or something? Using the mouse to focus overlapping emacs frames just sounds like a window manager thing in my head.