Some questions about the main window:

How do you generally set up a QWorkspace as the central widget of a main window? Is it possible in Designer? Or do I have to use code?

QDockWidget? I see you can do something in Designer, but how does that work, exactly? I can put them anywhere, and it'll be 'docked', it seems. Should I simply make it stick to the side with a layout for normal dock widget behaviour? Or might it be better to do the dockwidgets all-code?

In general, how much of the main window do you do in designer and how much in code (except, of course, the behaviour that can only be done with the code)?