The Problem is the lack of colour that we all encountered in Halo Reach. Over time people have givin some focus to this and many believe it could have been a top reason as to why the game failed to please aesthetically.
Although Halo 4 is after Halo 3, which had a rich and vibrant colour scheme, whos to say that it means that the next game in the timeline will follow? After all we are facing a new and mysterious enemy, one that could be far worse than anything humanity have ever seen! Since this is the case, 343 might feel as if a good way to show this is to alter the colours, to suit the atmosphere.
I hope they keep the Halo 3 colour tone, but if they are going to bring down the colour then hopefully it isn’t by too much, and that they keep a good colour scheme.
What would you prefer?