Doing so would not be trivial. In fact, figuring out a way of doing so would not be trivial.
Yes, but usually nothing worthwhile ever is.
The difficulty is that GIMP's plug-in system is dynamic and as plug-ins are added to the menus, there is no way of knowing what other plug-ins will be added to the menus (as subsequent plug-ins get registered). Or even to make any assumptions about which plug-ins have already been added to menus.
I am aware of GIMP's current approach to registering plug-ins. I chose to place my logo scripts under the File/Create/Logos (gimpchat.com), just under the default logos menu in 22.214.171.124. That just seemed to be the logical place for them, plus it gives this site a little free advertising.
The concept I envision would be a GUI that displays all the addon scripts with the ability to drag and drop them to menus other than the default. Would it mean a rewrite of the menu handling system? Yep, but C'est la vie. The way it stands now, there is no telling where the scripts will end up, as it's at the discretion of the author. I always end up having to mod scripts to place them in the menu locations I want. Certainly, there should be much more convenient way of doing that, especially for non-coders.