Change the permissions of Build.PL/Makefile.PL to not-executable.
Add a README to the distribution. It should contain a quick description of your module and how to install it.
Remove the POD errors. You can check for POD errors automatically by including Test::Pod to your test suite.
Error: IO-Multiplex-Intermediary-0.06/lib/IO/Multiplex/Intermediary.pm -- Around line 333: You forgot a '=back' before '=head1'
Add 'use strict' (or its equivalents) to all modules, or convince us that your favorite module is well-known enough and people can easily see the modules are strictly written.
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
Add 'use warnings' (or its equivalents) to all modules (this will require perl > 5.6), or convince us that your favorite module is well-known enough and people can easily see the modules warn when something bad happens.
This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.
Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.
Add a 'repository' resource to the META.yml via 'meta_add' accessor (for Module::Build) or META_ADD parameter (for ExtUtils::MakeMaker).