Why wouldn't random god work?
Okay, your rating won't go up as fast as if you memorized one god's build orders and just practiced everyday. Doing that will (probably) get you up to around 1750 and then you'll hit a brick wall. Playing random god earlier in your career will help you to break this door down.
Random god benefits people in many ways:
1) It keeps you away from build orders. No way are you going to memorize a certain build order for every god on every map. Instead, you will find a general build order for greek, egyptian, and norse on land and water. Then once you master these you will learn to customize them to fit the god's bonuses (as you memorize them) and eventually win consistently (at an even level) with any god.
2) It teaches you how to counter opposing gods. Many times in my days of whoring Odin I would wonder, how do you beat that? What better way is there to learn than to do it yourself until you lose consistently and see what beats it?
3) It makes learning much easier. As people beat you, you will see very clearly how they beat you as you now understand their god/culture much more thoroughly. If you were to be Norse and lose to an Egyptian, you would learn a lot more if you understood how Egypt worked than if you did not. You could see any loopholes in their strategy and be prepared to conquer it next time.
I've been Norse my entire AOM career, and only a few days ago I made the name cagedFury to play Random God on. And in a few games i've learned TONS.
That's right, I'm an 1850 Odin stuck at 1650 and I'm having a lot more fun than I used to.