@ Mori: I left more comments for you on the maps. You're getting to the point where most of your maps look like they should play excellently; you're nailing terrain -- especially forest, mountain, and river placement -- and you're doing a good job with creating interesting fronts and supply routes. Now you'll have to start working on the more advanced stuff, which is harder to teach and learn, and will require plenty of play-testing. Good luck, we're always here to help.
@ Morgan: Although the central towers aren't particularly contested, it usually isn't a good idea to place them so near to each other anyways. It makes it potentially too easy for one side to grab both towers, and a 2:0 tower advantage is as good as an auto-win if you don't have to heavily sacrifice something else for it (unit count, positioning, fund advantage). If it were me, I'd move the towers back a bit -- far enough that you'll only capture both once you have a solid advantage, but not so far that it's not reasonable to make a push for the second one.
The islands are probably a little too city heavy, and it will be quite hard to sustain a front there right now, since one country is going to be able to get to the island significantly earlier than the other. The amount of cities will also make it hard to attack into a side once they get a strong foothold, and if each country is able to control one island apiece, I think the map will fail due to only having one other front. The island fronts might work, if only because you did a good job positioning the shoals for drop-offs, but I would still cut down on the cities, and maybe reduce the airports to just 1 also.