You could always look at TemplateMapper, but I think it's not geared entirely to your problem. Still, if you come up with a normalized template, then you *could* make a map that incorporates everything your legacy has accumulated and then map it to your template. And it handles all those catalogs of things, as well as master and ref pages.
Shameless plug? Yes. Absolutely appropriate for your problem? Questionable... But looking in my plugins zone for the demo couldn't hurt... cud http://www.cudspan.net
