You are absolutely right, the usability of the command could be a little be nicer. But if you pick a wrong edge you do not have to star over again at all. It is possible to unselect a wrong edge by holding the <STRG> key an picking it again.
All in all I think it is a nice command, it is robust, you see what you get and you can use it for variants by only picking a section of a SheetMetal part.
Both videos are great solutions. I'm going to see if I can get these to work on my existing SW models- which are technically invalid solids in SW to see if things get corrected.
I also like the idea of the manual selection to build variants.