Kingpin Persistant Rage Charges

As of recent I duped my 5* Kingpin so I've been playing with him more and more and have actually come to really enjoy the character, but I've noticed the one thing he needs to really make him viable for more then just AW defense. It's really simple he just needs to his rage charges to be persistent from fight to fight (i.e. morningstar, mephisto, sabertooth, bishop, corvus, proxima). The biggest problem with him is that you have to have something bad happen to you in order to build up rage such as a debuff or getting evaded, if his rage charges persisted from fight to fight you could build up rage charges slowly through a quest and have him ready to go for the final boss. I don't think this would break the champion in the sense of making him to powerful because he burns up his charges as soon as he hits 8 so it would add a fun level of strategy by making you think about when to use him so you don't end up wasting the overpower buff on a non essential fight. I believe this would also make him a better defender because if you did use an evade champ against him and build a bunch of rage charges and die you would end up being punished because of your poor choices because you are now starting the fight against a kingpin that you have buffed yourself. Let me know what you guys think of this suggestion