absolutely, you should be learning new skills and techniques. the technology isn't standing still. if you don't keep up, you'll become obsolete.

how about more sophisticated web application frameworks? CGI::Application might be a natural next move for you. mod_perl? Object Relational techniques and modules like Class::DBI?

maybe branch out on the client end. take one of your server side apps, give it an XML-RPC interface, and make a GUI client in Tk, or GTK, or whatever that replaces the web interface but allows you to create a richer user interface.

check out other languages and their frameworks. see what you can learn from Tomcat and Struts. try to understand the design of Zope. figure out their advantages and disadvantages compared to your Perl based approach. can you figure out how to take some of their ideas and integrate them back into your development?

the fact that you can solve any problem with CGI and DBI doesn't mean that those are necessarily the best tools for a particular job. the only constant in our industry is change. other people are always coming up with ideas on how to make development faster, easier, and more flexible. you can either keep up and keep bringing in those new ideas, or slowly turn into a dinosaur and lose work to those of us who do keep learning the new stuff.