Id say the bow is probably the strongest when fully upgraded. There are only 3 enemies(that I can think of off the top of my head) that cant be killed with it and even then there are ways to get around that. Usually any run where i manage to upgrade the bow fully is guaranteed to reach high titanium. You beat the mk3 archers and sword/fire bots by kicking then shooting before they can get up. However despite my previous points i will agree that the bow is probably the weakest weapon early game. Its like one of those games where you get the worst weapon and you keep putting money into upgrading it and it becomes the best. ( by fully upgraded I mean energy to the max as well. This does not take into account fire arrows or the level 3 arrow width as those can be done without without to much impact on performance.)