I think with the first GL, they should have focused more on Oa, and the other GLs, when Sinestro puts on the yellow ring, I really didnt care, mostly because I knew it was coming, but also because they didnt explain it all, and actually my dad and I were debating the will vs fear angle after the movie, like, we saw will can be more stronger, so why did Sinestro put the yellow (fear) ring on if he knew it could be defeated? I didnt really care for anybody in that movie.
I dont think it all has to do with how well known a certain character is. I would have never considered Thor to be one of the higher up Marvel guys, and the movie made some good cash, Iron Man wasnt all the big until the movie, IMO.I think more people know about the Hulk, but both of his movies have only been ok. And now Marvel plans to test the waters with some lower down heroes and make like 15-20 min movies around them on a small budget. DC is still planning Flash and Wonder Woman movies, and I think they need to shoot them on modest budgets. One last thing, I think Marvel is more willing to take chances on lesser known heroes, just to try and get them out there, like Blade, Ghost Rider, Kick Ass, Jonah Hex, etc