I agree with @Revelate, the bunnies are very well balanced in my opinion. Squire Wabbit is the best 3* hero, Jack O’hare is probably the best 4* green all around (though others may be better in certain use cases), and Master Lepus is a strong contender, better than Thorne, Perseus, and perhaps even Richard. The bunnies’ defense reduction is meant to be a drawback, and your idea would actually make that factor another net increase in power. I really like the bunnies as they are, since they are the only heroes whose special offer both positive and negative effects. I hope that SG explores this design space further, creating more heroes with very powerful effects but meaningful drawbacks, so that players have to think about specials rather than mindlessly firing them whenever they are charged.
