Ok im going to be blunt about this
They made alot of mistakes in my opinion BUT this was their first take on a Halo game without boundaries and i do respect them for trying to stay with the mark that bungie has set for what is and is not a halo game. I wont go into all the flaws of the game but on the positive side there is alot of good things they did with Halo 4
One thing in particular is the Flood, while yes there are some adjustments that need to be made I believe it is a step in the right direction
As far as the story is concerned I believe they did a good job with it because while it wasnt as "exciting" as halo 3s it was still good and it kept me entertained until then end any more questions on my opinion you can message me