So, long story short: I love the item API, but one of the things I love about it is that instead of bits and pieces of functionality that happened to be needed, it's a very bare-bones system that gives you only the basic primitives you can't
implement in an addon.
I'm currently mostly distributing it with a wrapper that gives /bag access to it, but the ultimate goal of this library is to provide a general set of bag utility functionality to do all the stuff that we'd otherwise all be reinventing and rewriting at the drop of a hat.
I'm open to suggestions for things the library should do, changes to inputs or outputs, and so on. I'll try to remember to check here, but I am probably more active on the official forums.