Comments are a form of design + writing. So they are impossible to programmatically correct/critique. What can be checked, and is the issue with a lot of Perl preferences, is the regularity and verbosity.

Perhaps checking POD:comment ratio and recommending (at a LOW level) more POD if there is little/none but lots of long-ish comments. Perhaps scanning for run-on comments. Do the comments seem to come in than 2 (some "block" style, and inline) styles in the code; probably 2 is plenty. Perhaps putting a spell checker, if it's installed, on the comments and providing low level verbosity about what might be misspelled. Verbose feedback is sometimes nice even if you don't agree with all of it.

I wasn't sure how I felt about Perl::Critic for a long time but the more I use it, the more I like it as a sort of automated code review + anal retentive, somewhat stupid, pair coding partner.