I'm not sure how it'll work at this point. It's purely hypothetical while I focus on fixing bugs and adding features to the main game. Making new functionality for say, a progress flag, would require scripting to do anything outside what's already hard-coded. Either that, or the if block json objects to check if a certain one is present at any given step.
It could be possible to also set function references that are called at various events. So if a weapon has a OnHit event, it will call that function with a set of parameters in the data file. That would require a little bit of busywork on my part, but could definitely add depth and flexibility.
Sorry for my rambling! I'm not looking for an extra set of hands, but I would love to hear about systems to ease the modding community.