I think I may be stating the obvious here but, originality is seriously lacking. As much as I like duckhunt there are already too many flash variations existing. I found this one to be rather laggy as well. I read in your authors comments that the game originally had larger dimensions but was scaled down. I'm just taking a guess as to why I'm experiencing lag. I've tried it on two different machines and got the same issues. As hard as it is (being a fan myself) try to stay away from recreating sprite games. You are capable of making something great and original. You don't need gimmicks like retro games to get you by.