Also, to save you the trouble of searching, I'll add to the first piece of advice: here are a couple of custom maps where the AI develops quite well. It's convenient that their walkthrough is practically linear, and you shouldn't have any difficulties with where to go and what to do.
The Lord of War - it has both English and Russian versions.
Longest Journey
(Василь Симоненко. Люди – прекрасні)