Looks great! I love the look and 'feel' I get from the screenshots.
Only thing I can suggest, without having played it yet, is to add some more backdrop pieces, such as the sun, maybe some basic-fast day/night cycle so you can get some dynamic lighting/effects in there. Shooting stars and/or northern style lights in they sky, make the backdrop look alive at night. Also add Luna for the night sky. Lastly, have some Ai vs Ai combat in the backdrop, making it seem like you're in a larger battle and really give it that large scale action set-piece, really grab the attention of potential customers/players. Also give you a reason to add more epic explosions lol.
One last thing! Make sure the sound quality and mixing is top notch! This is something I've been working on and improving on in my current projects, really produce high-quality sound effect samples, bringing them into Audacity and than mixing them with various other sound samples, remix them a few times for multiple variations of the same sound effect, and make variations of 3D sound placement, since I don't think AppGameKit supports this yet as far as I know, so when an explosion happens on the left side of the screen, the sound fx plays from the left speaker and the sounds on the right play from the right side, ect.., ect... This will improve the feel, epicness and immersion of the game 100x over! You'll be amazingly surprised how good sound design.mixing can raise the quality of your game to all new heights!
Good luck! ...and think about me when it comes to testing.
My SO and I both want to try the game out and do some multiplayer action, lol. Sooo, email me if you want me to be a tester.