So, in the current game, resources are pretty straightforwards. Fertile land, build a farm. Gold vein, build a mine. Lost Library, reclaim it.
However, does anyone know if it would be possible to set it up so you could build different types of buildings for each resource? For example, Fertile Land: You can build a Farm (produces food), OR you can build a Horse Ranch (produces horses), OR you can build a City Park (produces prestige), OR you can build a Royal Garden (produces diplomatic capital).
The idea is to make building on resources to be a bit more strategic, and to let you build your empire more how you want instead of how the resources around you dictate. Want a lot of horse-riding troops? Build more horse ranches. Want a bigger empire with more people? Build more farms. Want to make this city just really big and populated? City Park. Want to play the diplomacy game more? Make a Royal Garden!
You could probably do this for most, if not all, of the resources, though fertile ground is probably the most flexible. Arcane ruins and lost library could probably be combined though at the least, possibly stuff like iron mines and gold mines as well, and even other minerals. Higher-value minerals just give you less per mine. Basically, how deep you want to be digging.