One reason I didn't want to upgrade PSE9 was my satisfaction with having a well-organized structure of keytags and keywords. But - Following versions went into the People/Places/Events order in an effort to organize these features. Now that I have upgraded at last, I find that the structure has become more inflexible. For one, I don't know how to re-alphabetize keywords. Nor can I find a way to reorder tags as before. Seems that the People/Places/Events just wants to mirror that initial 'improvement' in the PSE splash page. Yes, there is an Image Tags category for other subjects. Yet there is no indication that one can add these and have them appear on the Any suggestions?
I stayed with PSE7 well past the time to upgrade, basically for the same reason you described. However, I decided to forgo the predefined tags of People, Places, and Events and continue to use those tags that I had been using all along. Your existing tags are in your metadata and, if necessary, you can recreate them in the new version of Organizer. It's a little extra work but well worth it.
Before you upgrade, export your tags from PSE9 then import them in the newer version.