in reply to cpan mirror soft links...
But I'm wondering, does any part of CPAN require the symlinks exist for module installs?
No, it doesn't.
minicpan doesn't create them and the resulting mini CPAN mirror works just fine. As marto said, it sounds like that is exactly what you want, and it's already written for you and well-tested.
And if you want to include the latest development versions of distributions in your minicpan mirror, use CPAN::Mini::Devel.
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