Depending on the game - I sometimes prefer those positions. When possible I like to be able to focus everything on one front.
Build up to that point where you think the AI hasn't exceeded your power by 10 and then take a city. If the enemy is close, defend like hell - hoping the benefits of defense offsets some of the power difference. If the enemy is out exploring, take a couple more cities and work a war of attrition if you can exceed the enemies production base.
This specific map is pretty drastic, but might still be fun if the AI is at a high difficulty level.