The Superman/Doomsday film had some awful animation; the ugliest looking Superman I'd ever seen with most of the other main characters looking emaciated.
Batman: Gotham Knight was a compilation of several short films, some of which were okay, some were not and none were great.
The New Frontier...Well you all know how I feel about the New Frontier

WW had all those films beat. The animation was top notch. It took the WW from the JL animated series and improved on her, everything from her look to her actions, to her voice (If you guys recall in the first two seasons of JL: the animated series, most of the main characters had almost no emotion in their voices at all). The story was surprisingly deep and somewhat graphic for an animated kids film. It contained some hefty themes such as implied rape (Aries forcibly impregnating Hipplyta), women's liberation/feminism, mans capacity for war, and isolation vs. communication, graphic deaths, decapitations -one of the most memorable was Hipplyta lopping off the head of the son she had been forced to bear for Aries. That's not to say that the entire film was one big soap box rant. The story was punctuated with lots of great one-liners that didn't feel forced or lame.
The two main characters Kerri Russel and Nathan Fillion played off one another so well that it made their respective characters all that much more enjoyable to watch. Also, many of the other characters had many dimensions to themselves as well. Artemis wasn't just a narrow minded man-hater who worked out obsessively, Hippolyta made several difficult choices throughout the course of the film, hell they even managed to make their main villain, Aries, a somewhat sympathetic character which is a difficult feat to do in any medium.
Also, the battle scenes were spectacular. The film opened with a war between the Amazons and Aries' armies. Later on we got to see wilder looking demons emerging to battle against WW and the final battle took place in Washington DC where an army of demons, after soundly defeating the U.S. armed forces, fought against the Amazons. Nothing anti-climactic here at all.
I give this film 4.5 stars out of 5. It was that f'ing enjoyable.