Project Wizard - allow in existing projects

I think that it would make sense to (re)use the Project Wizard workflow in existing projects.

Use case: Customer built an annex or bought the next door apartment and joined it with the existing one, now I need to extend the original project.

(Or I just forgot a room or some functions.)

Why not leverage the existing wizard workflow for this?

Of course, the wizard itself could use some improvements. I suspect it's not used very often right now. One of the reasons might be that it's (potentially) useful in this one limited scenario (project creation).