I learned using SU on a computer with a quite small screen so the only dialogs I have opened are Components, Layers and Materials (Always in that order).
I try to keep the toolbars clean to not clutter down the UI. Some people recommend getting rid of all toolbars and only use shortcuts but I guess having a few makes the window feel a bit warmer and more like home to me.
Already a few tools in the advanced toolset are outside my laptop screen (walk around and section tool). It doesn’t really matter to me though since I’ve never really used walk tool anyway (eye tool + mouse wheel is so much easier to navigate with) and I have the full section toolbar open which also toggles section cut and plane visibility.
The 5 leftmost toolbars above the viewport are more or less the same between Sketchup versions and computers for me. Those to the right are usually for plugins I work on but sometimes include other toolbars as ThomThom’s solid inspector in this case (when I think of it I really should place that one further to the left and make sure to have their on all computers I use). Some times I have undocked toolbars but that really just when I have it temporary visible, e.g. when testing a new plugin or when a plugin’s toolbar is too large to be permanently open on my screen.