I, too, am curious how everyone uses Opus. The forum has few examples of this so I'll respond to your use case.
I have a multi monitor set up and launch Opus by double clicking on the Win 10 desktop.
I use a single default Dual Lister in details mode, not minimalistic, and augment it by using Tab Groups for different workflows. I have two standard toolbars open all the time and don't use the tree.
I have a few other Lister Layouts for other computers with different screen resolutions. I have no icons on the desktop instead using True Launch Bar to make all programs accessible from the Windows tray. I don't use tags.
I also extensively use Everything partial searches with filters to, eg., find a file and click on the path in Everything to go to it in Opus. For this reason I don't use tags or color coding because I can quickly find files or folders with out doing extra work.
If you want more detail on my setup see: