Hi Gary,
You're in luck, there is a feature about 3 months back that allows you to do just that. When you import a single folder in MC17, in the bottom of the window you can add additional tags to the import.
I hardly have problems myself though, when I import a set of files and the "Recently imported" list shows up, I just select all the files and tag them all at the same time. (i.e. I do not have to tag files individually if that's what you mean by tedious)
