Dana's a great guy, and easy to work with if you've got some good ideas. Have you considered forking and creating a pull request? Or making a request by emailing his PAUSE account or by raising a Github issue?

To work on code in Math::Prime::Util you're going to need to learn some C, and Perl XS. My experience working with Dana on some pet projects a few years ago, as well as attending a Perl conference talk or two of his, is that he's thought Math::Prime::Util through very well. But he's never struck me as someone who would be unwilling to make further improvements if they're sensible.