I agree with another poster that this would be a better short novel than a game. If it's not a ripoff of something already written, I see the bones of a good nonlinear-style book, which could possibly put into a game in a different format - something like Thousand Dollar Soul.
It looks like collision detection was implemented in a really bad and lazy way. Units in one row shouldn't block shots at units in a another row - from the bowman's view they don't share the same line of sight.