This map is surprisingly well done, I enjoyed it about as much as I enjoy any tutorial (don't really like tutorials, but this one is an exception, the Age Of series had great tutorials
)
The terrain is, as mentioned before, rather flat and uninteresting, adding some doodads and perhaps a bit of variation to the terrain would help remedy that, though. Although I do know that the terrain in Age of Empires 2 was kind of flat as well, doesn't mean you can't add a bit of variation on that within your mod :3
Something I notice is that the Militia have 400 health and the Knights have 100 Health. If I remember correctly, Militia should have 40 health. I'm guessing this is just a typo, but a typo that had a massive effect on the game. Do be careful of typos, especially in statistics
I am giving this 3/5, as it is just a tutorial and there are still lots of things you need to add, but it is playable and very much useful :3
Good luck with making more campaigns