I would like to see a 'promotion' system, similar to Fire Emblem(a system where you can upgrade a unit to an advance class). I noticed that you already had somthing similar to these advanced classes(e.g, the crusader could be called an advanced class of the staring soldier). I would like to see this because I would like to keep the same units throughout the whole game. Also, the resources you used on the 'lesser units' feel wasted since there is an unique unit waiting for you. I hoped my comment helped. Keep up the good work :).
The gamplay was slow and felt clunky at times. The ability to reverse the level and music made the game more interesting. Ultimately I didn't enjoy the game, regardless of the level and music reverse twist.