The Toolbar/Sidebar Interface Issue

I try to put myself in your shoes and in your way of working, and I can understand your point of observation. So since I agree with the perspective of @ideasman42 and since we are talking about a software and with programming we can do magic …
I would propose an automatic system of appearance and disappearance of property tools (similar to how it was for the top bar)

I think of this embryonic draft:
"When you activate the sidebar and you are in the “sidebar properties area” or you are in full screen, all the tools related to the 3d view, switch in the sidebar, otherwise they remain in the " properties area " …

In addition, customization options can be added to preferences for both redo and other tools.

I think a little bit of dynamism doesn’t hurt, and satisfies everyone.

for a better adaptation to this “switch”, I think, that at the design level it would be useful what was proposed here, with a sort of unification of the property buttons and the addons area …