Good choice IMHO.
I'd suggest to make good use of SSI (server side includes) so that footers, headers, navigation etc. are included from an easier to manage spot.
What I do nowadays:
every page includes footer, head, header, navigation and advertising from a file with a very slow increasing version number (actually only increases when I need to edit all pages for the change).
every of those files is set to again parse SSIs as needed and/or includes the references to more volatile things like the CSS: those get a version number based on a YYYYMMDDXX numbering scheme so that I can let be cached "eternally". When I update them I only have a few files to update that reference them.
Aside of that I make sure all the files are valid xml so if I ever need to automate a change, I can and have the tools to do so easily.