@billrey and I discussed this before and we’re both in favor of a tabbed interface that allows more conventional interaction. E.g. you could drag editors to different “tab-stacks” (areas), close areas by removing all tabs, pop-out or un-dock windows with drag actions etc.
Like this proposal points out, such a design doesn’t necessarily violate the non-overlapping principle - which is a strength of the Blender design in my view.
This is a very conventional way to manage windows, which I think wasn’t that common during 2.5 or was out of reach back then.
E.g. even Pixar’s Presto appears to have something like this:
(screenshot taken from this presentation)
There’s of course a big design discussion to be had before this becomes reality. And although I’d love to see this in Blender, I don’t think it’s something we can or should look into before the end of the 2.x series. Until then our focus should be on wrapping up the 2.8 project and making sure other module agendas don’t come to a halt due to usability questions.