Something for the AI team to look into, and perhaps further improve the AI behavior. Testing these community maps on hardest difficulty, there were considerable differences in difficulty.
Below, this generated map I have created. Hardest difficulty I found to be easy. There are many elevation differences and paths to opponent. I found with testing my map, the AI became confused throughout the match when I built walls in the inner-lower center of the map where the sacred sites sit. I witnessed AI moving back and forth rapidly in trying to make a decision.
To a Higher Pass - Mods - Age of Empires
When playing this community map on AI hardest difficulty, it was a challenge and I lost. It seems the AI is more tailored towards open maps. This map is very open with hills and no plateaus.
Misty Plateau - Mods - Age of Empires