Excellent depiction of Sinestro
For a cartoon, they gave Sinestro a surprising amount of depth. He has almost Byronic touches at moments, like his comment "I went into this alone, and I end it alone" (or something like that). Also, very effective on their part to given him a reverse-GL yellow uniform. He really made the film. In many ways, it was more Sinestro's movie than Hal Jordan's.
Hal Jordan himself could have used a bit more fleshing out. The movie wasn't bad in this regard, just a bit lacking. Still, he's my favourite GL by far.