@MrB: It is not possible (and not planned) to group panels, like it is in Scribus 1.5.2. The idea behind is really simple, you has only one place where you can activate the panel which you want - by click on icon bar. In the current QDockWidget you can stack single panels but you have to find the right icons (tabs) to activate the panel.
The current IndigoDock doesn't support multiple Docks, but I have planed that for v1.2
@a.l.e: I'm not what do you mean with collapsing/expanding dialogs. Do you mean the panel itself or the single collapsable content within the panel? If do you mean the content I agree, it is not progressiv but we haven't to use these control element
I prefer to keep the collapse/expand function of panels, because every panel can be really huge and not all features of these panels are permanently in use. That's the reason for the advanced mode of every panel.
@All: I'm currently working on control elements for the panels. I could finish the graphical AnglePicker and the LabelWidget. The LabelWidget allows easily to add a icon and a widget. Furthermore you can set a string or another widget instead of the icon.
Take a look to the latest version on the attached screenshot or in GitHub repository.