it's always the same with online shooters and their big fans, they say "yes yes we want changes, the franchise needs to evolve" but when you take out everything they complain about it is pretty clear that they don't really want changes and i understand that because they love a certain game so much because it is perfect for them as it is and if something changes the chance is very big that it will be worse for this person.
maybe they have a few points they really want to get changed but that would be something some other fans would complain about then haha. i mean, if halo 4 would be like he wants we would have the same amount of complaints on the internet, i'm pretty sure about that.
with that said, i personally would love to get an almost 1:1 copy of halo 3 just with other maps and a new singleplayer but that would fail hard nowadays.
