Is it possible to enable food imports with other requirements? For example, being able to build them if you own a province producing a lot of grain, like Alexandria? This way, you could grow your own cities thanks to Alexandria's grain.
Correct me if I'm wrong, but in EBII you don't need to conquer historically important places for Rome like Sicily or Egypt, because they don't affect the growth of your other cities (or the size of your army, but that's another story) thanks to their grain.
Sadly, trading in M2TW isn't very deep, so I think anything giving importance to resources could be a nice addition.