in reply to choosing modules for web site

I may just be getting old, but ... there is almost certainly some existing piece of software that you could use, instead of creating something altogether new from scratch.   (Even using CPAN modules.)   This has become a classical “build vs. buy decision” that, due to the rather prodigious number of packages that are already out there, almost certainly will not fall to “build.”

Even though this is a Perl forum, my first suggestion would be:   “evaluate the functionality first, and the implementation second.”   If you can find what you are looking for, and it works, and (better yet...) you can pay someone else to support it, then this is probably going to be your best approach, and you don’t have to care so much what language it was written in.   If you can find a suitable “software as a service,” then you are only interested in the results... and you have a binding legal contract (don’t you?) that says you must get them.   If you conclude, for whatever reason, that “a Perl implementation, on a computer that we own,” is most appropriate, then once again you want to push for what is the highest-level implementation:   the one that gets you as close as possible to your destination without work on your part, and the rest of the way with as little more work as possible.

Finally, I would encourage you to be as specific as possible.   Actually create a detailed, hypothetical, project-plan.   The research will be worthwhile.