as almost everyone i agree that this is a great TD game, however, i find the hero's attack kind of weak, as with the big hammer guy, he can tank very well, but he is kinda weak when attacking, and the bow hero well....
she just deals almost no damage =\
the ninja, healer and wizard (maybe some more characters) their defense should be upgraded, i like the ninja but he just gets 1 shotted by almost everything :|, same for the healer, and the wizard also a bit