I don't watch too many TV shows, but even I can tell that Avatar: TLA is perfect in pretty much every single way. The animation is spectacular, the action sequences are fun to watch, the writing is ingenious, the voice-acting for each character fits perfectly and is well done, the script is clever and extremely funny at times, and all of the major characters (and even the ones who aren't as pivotal to the story) are developed so effectively. One of show's greatest characteristics is its perfect balance in tone between humor, darkness, and humanity. The way it does this is by creating a nice variety of relate-able and fun characters and having a great story that ultimately brings them all together in an epic tale of loyalty, identity, perseverance, loss, and love. To sum it up, this show pretty much has pretty much anything you could want in a show.