When H_Oskar first started working on this Mod, one idea he had was a castle improvement that would provide a defensive benefit to tiles. When implemented, this idea did not work, as the AI did not seem to want to build them.
The idea is a good one, and I think I can implement it in such a way as to make the game more interesting.
Here is what is involved:
1) A new resource needs to be created. It would spawn in all terrains. The resource would be called Redoubt and represent naturally defensive terrain within the tile that could easily be made into a strong defensive position. The Redoubt resource would not provide hammers, gold or food, but would provide a defensive benefit of +10% above that given by the natural terrain. It would not be tradeable. I would use the city ruins graphic, most likely.
2) A new improvement must be made, called Stronghold. It would be gained with Stoneworking. It would use the fortification graphic, and would provide the same defensive benefit as fortification from the base game, +25%. It would be an improvement for the Redoubt resource and provide +1 hammers and +1 gold.
3) The Stronghold improvement would subsequently grow into a new improvement called Baronial Keep similar to the growth of cottage to village to hamlet to town. The defensive value would increase from +25% to 50%, and the improvement would yield +1 hammer, +1 gold and +1 food. It would become available with the Fortification tech. The Feudal Lords Civic would enhance this by +1 food, the Dynasty civic would give +1 gold. I'm not certain which graphic to use... perhaps the Citadel Castle for Spain from Warlords, or the Castle from the regular game.
4) The Baronial Keep improvement would subsequently grow into the Royal Castle. It would be gained with Engineering and provide defense of +75% up from the Baronial Keep's +50%. The improvement would also gain +1 hammers, +2 gold, and +1 food. The Dynasty civic would provide +1 gold, the Feudal Lords civic +1 food. Again, I'd use the Citadel of vanilla Castle for the graphic.
One thing I don't like about the game is that the AI doesn't build Fortifications. I think it will do so with the use as a resource as improvement bait.
I think its a makes sense as an idea. Many castles and such were built for defensive purposes. Most famous ones are not found in cities. So a castle improvement to suitable defensive terrain makes sense.
I'm willing to work at the XML files to implement the above, but would like to find out others thoughts about the idea... I think it is workable simply via XML, but am not absolutely certain.
Is it a good idea?
Should I work at implementing it?
Are there any changes needed if I were to implement it?
I've a couple of additional ideas, but they likely need python. For instance, I know certain Fortification mods allow forts to provide culture... this would make sense in this idea, as Royal Castles, especially, spread royal authority, power and influence. This would be an interesting idea.
Anyhow, should I do it? I'm willing to give it a go if there is enough interest, and if people don't think the idea is idiotic.