Massive sympathy with your post. Having administered a polyglot system with multiple AIX versions, SCO, and Windows NT, I feel the pain of when you need it, all you have are the core modules.
Like you most of the Perl programs I've written are hacked together for my own use, or under my supervision. I'll try to remember when offering assistance on a Perl question to provide a "core only" solution and offer modules as an alternative. Modules cut hours, days, weeks off the development of some projects. I always look at the CPAN directory for a possible solution before I begin formally coding a project. But you can't always count on being able to run those modules because of system limitations.
Good post, and good points man.
Poetic Justice