Since we are moving fact parsers from plugins into core and this is nothing else than fact parser extension, maybe we could consider this feature when refactoring our fact parser plugins creating some way to hook into importing process and then merge this plugin into core. This plugin is so small and does some monkey patching that it is probably worth taking it into core now.
We do have something similar in discovery called import_hook it could be actually designed in a way that would be beneficial both to this plugin and discovery.
Long-term, I would love to see discovery being merged into core as it does a lot of fact importing hacks too. Since we are moving other fact parsers too, discovery should be not different as it is basically a puppet importer with few additional extensions (handling of special discovery_xyz facts).
@dmatoulek what you think?