Its so pleasant to find such resources spreading throughout the community. Perl is one language which could've died easily given its undeserved write-only reputation, but its thriving and making some very cool new stuff while steadily negating the argument of being line-noise (Dancer comes to mind as an excellent project to both read and use).
While Modern Perl and Perl Best Practices seem to be now the defacto texts to follow in this field, I highly suggest to also supplement your learning of good Perl by reading Perl Medic by Peter Scott. While its main purpose is how to maintain a legacy codebase, its an absolute gem when it comes to what type of Perl code you should be churning out.
I'd really like to follow up on this recommendation: I used Perl first as a kind of sed and awk on steroids in the dark days on a VAX running BSD 4.3, wrote simple CGI in it in the early 90's then later recoded a fax gateway in Perl 4 on Solaris 2.4. Like many people, Perl for me was a useful tool, but regularly unreadable, and admitting of very few good practices. In the end, I moved across to other domain-specific languages and only dived into Perl infrequently for data analysis tasks during the last 10-15 years. Writing the same old unmaintainable, unreusable, script-like code, and hating it.
Modern Perl is a revelation! While the first hundred pages are a crystal-clear recap of the basic language (and I found at least a couple of things there that I didn't really know about), the chapters on modern object-orientation (using Moose), exception handling, testing, maintainability, and what features in Perl 5 to avoid are all pithy, to the point and well-argued.
If you're a (self-exiled) Perl coder like I was, give this (e)book a read and see if you might jump back in. I have - and would second frameworks like Perl Dancer as fantastic examples of what the Perl community is up to these days.
I was excited by the title and bought the book, but have been quite disappointed. Nothing especially fancy in there; things like function dispatch tables.
Regardless of their slightly dated information, I'd add to your list the standard 'Perl Cookbook' by Christiansen and Torkington. Likewise 'Programming Perl' by Wall, Christiansen and Orwant. While not perfectly up-to-date, the reader should be able to immediately use the code and if necessary refactor later. Come to think of it the editions I have are of a same vintage as 'Medic' so same advice applies...
While Modern Perl and Perl Best Practices seem to be now the defacto texts to follow in this field, I highly suggest to also supplement your learning of good Perl by reading Perl Medic by Peter Scott. While its main purpose is how to maintain a legacy codebase, its an absolute gem when it comes to what type of Perl code you should be churning out.