eh, I never thought the Marauders were that bad. Kind of like the popular jocks, but not bad people at heart. We shouldn't forget that we see them from Snape's perspective, and yes, they're awful to him but as Lily says when he tries to apologise he's already sympathising with Voldemort and hanging out with "that" crowd at that point. Doesn't excuse the Marauders bullying of him but it makes sense why they dislike him.
I actually think it would be very interesting to see a show/film about them. All those kids at Hogwarts bickering and competing in Quidditch matches, and only a few years later, some of them end up fighting each other in battles to the death? It's pretty fascinating. The point where Sirius completely breaks with his family, which isn't just personal due to the circumstances but also about choosing his "side" in the war (does he realise that, at 16? How does he feel about going on to fight his little brother?), when and where Peter grows resentful enough of his friends to lead them to their death, Remus' struggles with keeping his secret, all of that would be really interesting.