WRT #4, I'm of two minds on the subject. On one hand, I tend to scoff at the "no installation needed" at a day and age where users have machines infested with Java and Flash installation (often 2 or 3 of them) as well as other runtime environments. Maintaining a solid CPAN installation is usually easy and simple, and getting easier and simpler each day.

OTOH, I encountered several instances where what was supposed to be a simple module turned out to be a full blown framework with Moose on top (hello, Jifty). This immediately get a "to be removed/replaced" tag.

In regards to the entire post, as much as I'm a supporter of Best Practices Preaching, it tends to be considered as gospel, to be followed blindly, rather than "general rules that you may benefit from following". There are cases where all the above reasons are not valid, and, as mentioned above, cases where those should not be followed at all. There is no One True Rule, despite the many claims here, and elsewhere.