If you can get HTML::Template on your server it supports almost exactly the "parse template/fill in content" methodology that you've just described (only the tag format is slightly different): 
    <TMPL_VAR NAME=PATH>

[download]
In response to your original question :
Considering that most webhosting companies do not offer solutions such as embperl, Mason, Apache::ASP or others of the sort, what is the most efficient way to work with, build and maintain these websites?
I would not let "webhosting feature availability" influence my decisions in any major way when it came to features that would severly affect the design, development, maintenance, architecture, scalability, and performance of a site. I first decide what are the right tools to use to make the site then ask who can provide me with these tools. If a company can afford a 7 person team to develop a website then they can surely afford to get server(s) configured they way they require to run the site. You are already placing requirements on the server by making the choices of perl, DBI, and a database (w/ apropriate DBD module). Requiring a few additional perl or apache modules is not asking too much. Making an architectural decision of such importance based on provider availability could lead to a support/maintenance nightmare later on. It is well worth it to do things properly up-front to save yourself pain later on. Choosing an inferior tool just because its convenient is not the right answer : I don't see any saws near-by, but I do have a bunch of hammers, so why don't I use one of them to cut this 2x4.

Webhosting is a competitive market and it sounds like you are developing a non-trivial site. Hosting your site could mean a lot of income to whichever web-hosting provider you use. They should be willing to provide you with the tools that you require in order to get your business. If "most webhosting companies do not offer" what you need seek out the ones that do and give them your business. Other developers will make the same choices as you and the providers that offer better services/features to the site development/maintenance team will flourish.

In reply to RE: Design vs. Code vs. Maintenance by lhoward
in thread Design vs. Code vs. Maintenance by BBQ

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