Moving ahead, there are only a couple of things that I'm monitoring at the moment. The first is that the game doesn't just reward advanced planning, it requires it -- if there's an action you want to take and you're not in position to take it configurationally, it can take several turns to set it up, and this can be frustrating. It's not necessarily a "bad" kind of frustrating, but it may be advantageous to loosen the game up a bit.
Second, I'm still not perfectly happy with the spatial elements of the game; there's a a certain equivalence to the territories that may not make the geographic aspects of the game as interesting as they could be. For example, if I need a crops-producing territory, I'm as happy to get Libya as Judea; there may not be a strong reason to prefer one to the other. But my bigger concern is with the structures system; the structures are supposed to modify individual territories, so you're supposed to care about where you place them. But in practice, as long as you have a Colosseum somewhere it's fine; same for a Wonder, etc.
All along, the board has mountains and rivers drawn on it but these are just decoration. However, my thought is that these could become active elements of the game in concert with the structures system, by having a couple of structures take maximal effect when placed on certain features, eg a quarry in the mountains, irrigation on a river. Tying the effects of a structure to its immediate environment, ie by having the structure's power affect only the territory in which it is placed, or its neighbors, could help emphasize this. If some of the structures also "boost" one or more actions, this could be a way to reduce the "advance planning" problem mentioned above (sort of -- you still have to advance-plan to build the structure!).