Keaton was a good Batman/Bruce Wayne. Kilmer was a good Batman but not a good Bruce Wayne. With the exception of his over the top raspy voice, Christian Bale was great at both.
I’ll give you the not a good Wayne just because he looked like he was 20. But even then, I thought he had the right blend of camp, angst and attitude.
I know its not a popular take on The B’ster, but it worked for me.