We longtime (read "old") fans of Batman have been waiting for a cinematic Batman that reflects the greatness of the comic books. Unfortunately, we have had to put up with the worst attempts to realize this great character. The movie serials were atrocious, the Adam West show, although entertaining, treated the character as a joke. The Filmation cartoons and the Superfriends were watered down. The more recent movies are a mixed bag. Then, along came BTAS, and we were finally satisfied.
Everything, from the look and tone of the animation, to the stories and voicework was first-rate. Batman is the Dark knight Detective. He's not a guy in a rubber suit. He is skilled, intelligent, obsessed, tortured, and dedicated. The villains are evil, psychotic, and just plain loopy. We have Paul Dini's wonderful creation of Harley Quinn, the first inspired and interesting character, since Denny O'Neil created Ra's al Ghul.
The creators took their cue from the legendary Flesicher Bros. version of Superman, with it's Art Deco stylings and darker color palette. It took its story concepts from the work of Bill Finger, Denny O'Neil, Frank Miller, and Steve Engelhart. The music was inspired by the wonderful Danny Elfman music from the Tim Burton film. The voicework featured outstanding actors, with mature direction from Andrea Romano.
The only criticism I can level at the show is that they avoided doing a complete episode revolving around Batman's origin. Granted, the broadcast standards and practices limited how much they could show, but they found a way to present Robin's origin, without sacrificing story. They did present elements, but I would have liked to have seen a complete episode, with his training and "year one" adventures. The Superfriends episode, "The Fear" presented more of the origin than BTAS ever depicted. Still, it didn't detract from the overall effectiveness of the series.
The series even improved on some of the elements of the comics. Personally, I never thought much of Bane, but I enjoyed the BTAS version, complete with the Lucha Libre stylings; Bane as luchador hitman, classic! The Joker was far more interesting here than he had been for some time in the comics. The Riddler came across as deadly, rather than a joke. Alfred provided more than window dressing.
This is the series that set the standard for all other cinematic Batman efforts. Thankfully, it removed the bitter taste of Joel Schumacher.