I agree, that would be really interesting!
On that vein, what kind of places would you suppose have their Keepers in this world? In pre-Christian times is was many natural features, and some human places (home, sauna, drying barn etc), but not every place had them. Would the Keepers have disappeared and now come back, which would mean that they appear for human places as of current humankind. Or would they have been there all the time, just hidden?
Or to put it in other words, would you suppose there could be a Keeper of the airport here? As it is, it’s not a notable natural place, and it has no meaning for the humans of Y91, but in the pre-rash times it could have held significance to many people.