It’s not 2004 anymore. Standards have changed. You can’t expect the same bare bones experience that Halo 2 was, it just won’t be as good. AA’s, Perks, Sprint, what ever it is, these are things that games have moved towards naturally. Sprint is a good feature in Halo, and I’m glad they’re keeping it. I’m not sure if other AA’s will return, but come on guys they were fun. And the progression system with Perks sounds cool (so long as it’s well balanced, which i’m sure it will be).
Get out of 2004 and welcome to 2012. Games naturally evolve and progress.