I'd love it if there would be graphical frontend to tmux or screen. Something that would look very much like a terminal emulator, with tabs and splits, but backed by screen or tmux, whereby each tab or split window would be a tmux or screen window. And the awesome part is that when you're elsewhere, you could ssh in and attach to that tmux or screen session.
How far you take it depends on what you'd want out of such a tool. Simple "New Shell", "Close Shell" buttons would be easy; overlaying draggable partitions would be more effort, and less elegant, but still do-able.
