Lol, please for the last time I never said you play as Chief for 10% of the game, I don't know how long you play as him. It was just described to me similarly to the ratio you'd find in MGS2 for example. I won't stoke anything more, I love Halo like many others here. To re-clarify and just finish what I said, this person told me they want to get into the e-sports scene a lot with H5, or that it's a big goal. Small style arenas are a focal point. I asked if ADS was on all guns, replied "pretty much". I don't know if it's purely cosmetic or what, but I asked just now to further clarify if it's even on things like the plasma rifle/pistol, etc. Said that ADS (again don't know if it's just cosmetic or something) was a big focus in development, now says it may just be limited to a few weapons, but that it'd be a strange thing to focus heavily on if it's limited. Assault rifle does have it though. He also reiterated that all the negative reaction might change things, Microsoft's playing it very safe and there's still 'plenty of time'. Anyway, I don't like being vague so I hope that helps a little? Probably would have been better to wait until seeing it in action before saying anything.
http://www.neogaf.com/forum/showpost.php?p=138058108&postcount=2060