Alex, don't feel as if the weight of the burden of proof (of concept generalization) has to rest completely on your shoulders. I realize you already agree that curiousity and your own interest can be enough reason to pursue a topic or generalization, but...
Isn't it the same as asking a question on mathoverflow about a topic which is interesting to you on its own merits, and finding out about the existence of either a longer history of it based on a parallel set of definitions or other possible applications of it in other branches of mathematics or physics? I had been working on a particular topic, but having approached it from one direction I could only perceive the question from my point of view.
Even my attempts to research it found nothing initially because I was using the wrong key-words to look for similar work on my topic. It turns out that there was a long history of work on the topic using different terminology which I was not aware of.
Perhaps giving a short summary on mathoverflow (as a different question) of the generalization which you are working on woukd provide you some different points of view from other mathematicians.