While the AI has improved due to the changes in how the AI handles economics, consolidation, diplomacy, and stability, the AI still seems to lack any real ambition outside of seizing de-jure territory and pushing their own claims, especially in feudal Europe where rulers do not have access to any easily obtained CBs like Conquest or Holy War. When I was thinking about how the AI can be made to have greater ambition, I realized that players tend to set their own ambitions based on some sort of preconceived objective. In an attempt to recapture this, I've come up with the idea of "AI Ambitions." Essentially, an AI will pick an ambition based on any number of factors, and there could be different "types" of ambitions, which I'll call Decision Ambitions, Historical Ambitions, and Miscellaneous/Generic Ambitions.
Decision Ambitions are what they sound like, the AI tries to meet the requirements to take a certain decision. For example, a West Slavic AI might pick the ambition to take the "Unite the West Slavs" decision, resulting in them attempting to conquer the region of West Slavia and create one of the West Slavic kingdom titles to use as their primary title. However it can also include smaller ambitions such as a tribal ruler wanting to become Feudal/Clan.
Historical Ambitions are based on real life history, and might be more difficult to implement. The purpose of these ambitions is to organically set the game on a historical path in a flexible way that's adaptable to whatever butterfly effects might happen over the course of the game. Examples of this would be an ambition for Harald Fairhair to unite Norway or for Central Germanic rulers to form the HRE (which would also count as a Decision Ambition).
Miscellaneous/Generic Ambitions wouldn't be tied to any specific decision or historical event, and would include generic things like "Obtain a title of a higher rank than your current titles."