Answering your question whether it is right or wrong to import ':all' methods into client code, I think it depends. I like importing all methods for simple modules and in cases where I am absolutely sure no conflicts would arise. Examples of a few such modules are Date::Manip and Data::Dumper.
in reply to Namespace Pollution
One way to avoid having to deal with the namespace pollution issue in your code, you might try to make use of an OO interface to your modules. Unfortunately not all have one implemented for them, in which case you might resort to selectively importing only the most often used methods, leaving the rest outside of your namespace ;)
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