Affiliation: Order of the Phoenix
We've learned bits and pieces about James Potter over the course of the Harry Potter series. First we saw him as a loving dad (Books 1 and 2), then as a mischievous Fred and George-like Marauder (Book 3), and then as the good guy who saved the ungrateful Snape's life (Book 3). But, in the later novels, we begin to question James a bit.
In Books 5 and 7, from Snape's memories, he appears to be almost a Malfoy-like character, full of arrogance and possessing a ruthless bullying streak. He emerges as a character that's truly Snape's opposite: James is confident where Snape is insecure; James seems to be cared for and come from a loving family, while Snape's family is poor and unloving; James is handsome and popular, while Snape is neither. And, we must admit, we don't always like James more for his differences from Snape. We feel a lot of sympathy for Snape, the underdog, and find ourselves rather pleased when Lily calls James an "arrogant toerag" (33.174).
At the same time, we have to recognize that much of the information we're getting about James comes from Snape, and the two were clearly rivals for Lily Evans's affection. It's not hard to read between the lines of Snape's memories and find an immature James trying to show off to his crush, Lily, and cut down Snape out of jealousy. Dumbledore, Remus Lupin, and the rest of the Order of the Phoenix certainly were very fond of James and frequently assure Harry that James was a good person. And Lily, who seems to have pretty good judgment, wouldn't have loved the guy for nothing, right?
In the end, we get the feeling that Harry has come to terms with his father, and recognizes that, though he was a rather arrogant schoolboy, he was a good man and a brave member of the Order of the Phoenix. Harry and Ginny name their first child James, after Harry's dad.