Nothing to do with the recent discussion, but I just found
JRouteNative..... Going to be using that instead of ZRoutes for the Mechanos fort. Allows me to do several things, including setting units to require roads to move, setting them to be unable to move on certain routes, setting them to ignore the movement bonuses of a route, and setting them to use the bonus from one route, on a different route... So I could have, say, a Hippus Raider UU use the bonus from an (unused) improved road, on normal roads, giving them even greater mobility.
Edit: Also, might move the Bezeri away from a hard limit on the number of cities, to use code from JCityLimit to limit the number based on the Era... Which FF still uses a few of. Not sure how that'll conflict with religions, though.
Edit2: Jesus, wishing I'd gone through Jeckel's modcomps before now.

Here's another,
JCultureControl. Basically does exactly what I already planned to do myself, in that allows me to set a tag for an improvement that will automatically spread it's borders... No code to run each turn, searching out the improvements and then relying on a unit's promotions. Fort Commanders will remain, but they will have significantly less effect on the cultural borders.
Edit3: And another minor miracle.
JImprovementLimit. I get two things from this: First, Rather than needing a python check to limit certain improvements (Pirate Harbors? Bedouin Sits?) from being built next to each other, I can set a simple tag that does it all... Meaning the AI should be able to understand it, without slowing the game. Second, there is another tag preventing certain improvements from being built in cultural borders... I can easily see applying that to forts.