History:
I am running about 80 (and more to come) child portals off of one domain.  We created each site using a main site template.  We then got creative and did a skin page for each page on the site and put the entire package in as a host skin.  This way we can change the pages and upload the to the host skin package and all the sites change at once.  This is a sales site, so I wrote a custom module for the contact page that pulls the sales agent's specific information up to "customize" each sales agent's site.

Problem:
The client said "We'll NEVER change the structure of the site, just the information on the pages", hence the setup above.  Well, I really stressed this question and figured they would eventually not stick to that statement and I figured I'd cross that bridge when i got there.  So, what I need to do is create a new template with the addtional pages, when copy the template to each of the child sites.  I don't care about writing over everything on the children, except of course, any user information.

Is there a way, or a third party module to 'update' an existing site's template?  As always, any help would be much appreciated!

Barrett