Just popped some popcorn sat down and activated Waypoint and looked at the cast shots, behind the scenes and the TRAILER for Forward Unto Dawn. First. Was thinking about why they chose this suit permutation for the web series, and where it fits into canon timeline. Here's what I think. 
The series may take place during the time Chief was putting the Mjolnir  MkV armor through the trials that almost cost him his life due to  Colonel Ackerson exceeding the testing mandate and using 
missiles as detailed in Eric Nylunds's Fall of Reach.  The markings on the armor (the 117 denoting the participating asset and  the racing stripes showing his class) clearly visible to observers,  seem to bear this out. The hole in this theory is if Halo Legends is  canon, MC would have had to wear it into actual combat to rescue Halsey  in the episode "The Package". whatta ya think?
Also!
As far as the series is concerned. Done a million times. It's a classic 
coming of age story. Nothing fancy as far as plotline and or characters. But it will be epic in scope and mythos so it has that. And that's all it needs. 
I think it's interesting that the first ever live action effort from Microsoft/343 seems to be geared at the younger demographic, Not that there's anything wrong with that. Not every movie centered around 20 somethings has to be pablum (although, aside from Lord of the Flies, I can't think of any right this second) whereas Bungie's  
Believe  and we are
 ODST  and 
Remember Reach ad campaigns were a lot grittier and dramatic. When that pod opens and Tarkov steps out into a wall of plasma and giant aliens....or Listening to a Mother reassuring her son that "...It's only 3 days, I'll be back in no time" in the center of a doomed planet or hearing the terrifying accounts of the veterans "...for seven hours we waited in the dark hearing them hunting us...waiting for the Master Chief", ah getz CHILLZ, YO! 
Not sure how that bodes for any movie in the works.