As a long time fan, I've wanted a full adaptation into film or TV series of Halo for years. It boils down to a few things for Paramount to get right:
1) Helmet on:off ratio 99.999999:1
2) As much covenant blood spilled by chief and an MA5B assault rifle as possible in a 60 minute episode.
3) Stick with the Lore, there's books, games and comics already written with loads of material - there is absolutely no need to come up with a new story.
Unfortunately, each episode seems to be the reverse of point 1) (helmet on time looks like the sum total of the first 10 mins of the pilot +20 seconds across the next few episodes. Point 2) is also compacted into the same pilot opening sequence (I mean when are the grunts going to appear??). Point 3) well there isn't enough space in the comment section to analyse where this went wrong.
Also, Kwan is pointless.