Bottom line is that Shirley Walker was Danny Elfman's conductor during the late `80s and early `90s. That is perhaps the reason why she was hired. She knows Elfman's style and used it during the animated series. Zimmer/Howard made a more epic score. Elliot Goldenthal went for a more light-hearted, action theme score. Elfman and Walker both approached Batman with the same style and same idea. It is kind of pointless to debate this.
Back to the topic: The problem I had with Zimmer/Howard is that the character's didn't really have a musical voice. They did a great job creating the mood with the music, but Elfman also did this and gave each character a theme. Batman had a theme, Joker had a theme, Pengin, Catwoman, etc. In BB none of the characters really had a theme. The music was done to serve the film alone. At least Elfman gave each character their own musical voice aside from serving the film itself with scores like "Descent Into Mystery."