I like the game, am a big fan. My only problem with this map is that it is not strategical enough. By the way, I play chess so thats a heavy influence on my comment.
Anyway, I think units should have an ability to defend each other when they are linked by a movement circle. In the case they defend each other they both go to battle. Attackers should have a similair thing where they can send more units into battle, perhaps when two units can attack a unit.
Its only an idea but I could imagine playing the game would be difficult with the small gameboard.