Hi, just a couple of ideas imho:
-the cost of ammos for the weapons is very frustrating, better to make the weapon cost more (maybe MUCH more) but give it with infinite ammos.
-make the name of the location (just before the battle start) appearing and disappearing faster.
It reminds me a mix between "Defender" and "Battleheart" (for the graphic).
Very well made, good work!