Feedback: Excellent submod in the spirit of the original, I really like all the new things to discover and master. I am glad that after all these years there's still an active community working on this, as this game is one of the last left over worth putting time into nowadays in my opinion.
suggestions:
regarding forts, castles and citadels:
Therefore I'd suggest that the highest tier of the fort, the citadel, at least gives some sort of yield improvement, like 1 , or even 1 and 1 , or whatever you seem as appropriate (extra bonus with feudalism). The yield increase should be inferior to a specialized improvement, like f.e. a mine, but should still make that plot a little bit better than as if nothing was on it. As the player pays 1 solid gold for the fort commander, and leaving forts empty is just an invitation for a wolf rider swooping in and claiming it, I think this would not be unbalancing. Furthermore I'd like to suggest that the highest tier of forts also gives access to at least some crucial resources, so the AI will not have a fort on, let's say an iron deposit, and cannot use the iron beneath it. No chance for spreading or discovering, just access to this resource to the trade network. This might be unbalancing, maybe for multiplayer, which I don't do, but as far as i have observed the Ai will not neccesarily remove a fort from a resource even if it's the only one in their territory. Military resources like horses, copper, iron, mithril come to my mind there. A player will always try to get the full bonus from it, especially when this resource is next to a city anyway. Anyhow, I put this up to debate.
I agree with you here.
regarding resource discovering:
It has been said before, but obsidian discovered in mines is not so good. The reason why is that you will only discover resources you have already the tech for. So if you start building mines right away there is a high propability you will get stone, marble or obsidian before you have the tech for iron or mithril.
Alternatively the discovery rate of stones and such could be lowered.
Okay sorry for the long post, and all the typos I haven't found and I hope for many more years of mod goodness
As far as I'm aware, mines no longer let you discover obsidian, and mithral, iron, bronze would still not be visible if you don't have required techs. I'm not sure about marble or stone though...