Hi @ideasman42,
really glad, that this thread still gets some attention from you.
I am not sure on the form, how proposals like this normally get made in this forum. I also think that you have some internal style guidelines that should and would influence how this turns into a good extension of blenders toolset. But other than this long thread implies, there is alot of agreement in general on such a feature among most people in here.
To sum it up there are about three different proposals or concepts in this thread. One option has been to map it to the 3dcursor and give it some new modes, one is to have a separate pivot point visible all time and being completely separate. The third one is the one I think most people would agree on. It’s the one i’d personally prefer too and it’s the solution that can be found in a wide range of 3dtools out there.
That solution is about being able to activate and deactivate an “edit pivot mode” that changes the behaviour of the current visible transform gizmo. If the “edit pivot mode” is on it will change its own position and will not affect the currently selected meshpart. After the end of the editphase it stays at the modified position and orientation and can be used normally to transform the selected mesh parts. (The main aspect of this new mode should be that its possible to edit the pivot as directly as possible, so no 3dcursor setttings needed prior to it and no additional commands to set it should be involved)
Some early suggestions in this thread wanted it to be available in to be mapped in edit mode to a similar checkbox like the Affect Origins one in object mode also as a checkbox to toggle on and off. That could be a valid place to trigger it via the ui.
But it would also be benefitial to activate and deactivate it even quicker with one or more of the options proposed, may it be in form of a modifier key (sticky key behaviour) that can be hold and released, or small toggle buttons aligned at the gizmo itself as adaption of zbrushs gizmo or even with just its most simplest form as a shortcut for the toggle to turn it on and of as a modal tool.
It also should have an option to snap to meshparts of the current mesh or any other mesh too, maybe somehow like blenders measure tool snapping option and mainly thats all about it.
How are the chances that this could get implemented? What else can we do to support that idea? There are quite some good video demonstrations in this thread on how some other tools with this feature have it implemented.