Is there something wrong with the hardest AI?

Hi there,

I'm fairly new to this game (but played as a kid and played a lot of AoM and AoE 3) and I'm having trouble determining whether the AI is acting as it should.

Basically, when I play against/with AI, they build up a huge resource pool but they never do anything. Some of the AI do build infantry armies and attack and roll over the other AI players but mostly they just sit there and wait to die.

I've tried using a smaller maps but then they seem to just randomly send trickles of units (like a single ram + 2 knights) at a time or sometimes just sit there doing nothing again waiting to be provoked by another AI literally building in their base (and even then they barely lift a finger).

Are there map types/settings that bugs them out or am i just playing wrong? I would try custom AI some point but I hope this isn't the intended way the AI works!