What's the key to add a third column and have the others automatically resized?

Do other windows start inheriting the project drawer if older windows are closed?

Each window has multiple tabs - how do you tear off and replant them using the keyboard?

Doh, now the temporary horizontal split panes like find-in-project, the python console, etc, must be attached to a specific narrow window.

And so on. I like a multi window desktop and am certainly not a maximise-everything guy. But relying on the OS for everything is not optimal.