These mods add new elements of Gameplay that makes your games all that more interesting. The additions can be small, such as having Militia units rise when your civ is under attack; or it can large, such as adding the chance for civil war based upon happiness and alot of other factors.

With these mods, each turn can lead to interesting decisions with just as interesting consequences.
This collection might not be compatible with mods that overhaul every aspect of the game. However, these most likely will be compatible with conversions that bring in new settings into the game, with mods such as:
Faerun
Game of Thrones
etc.