im with the others here i feel that the hero's HP i way too low hes only useful from lvls 1-2 the rest i just keep him back and have my units kill. Suggestions:
-More Hp for hero
-More upgrades for units and hero
-Making it so that Getting defeated is not by getting your hero killed
-More Hp for Super units and normla units
Thats all for now hope you can fix it >.<