Here's what I saw...
The O-line looks like it's reverted back to the zone-control mentality that Barney seems to love and which failed so miserably a couple of years ago. They appeared to be so worried about their zone that they forgot how to pop the stray linebacker or D-back that happened to blitz. That might be the easiest way for a young line to learn to block but it's a failure in the long run, especially with a QB like Martinez who shouldn't be throwing out of a pocket anyway. A guy who throws the ball like Dan Quisenberry needs to roll out or he's going to be getting a lot of passes deflected at the line.
The D-line is too light and not providing the penetration that'll keep the opposing O-line from getting to the linebackers. Once those big hogs on the O-line get to those speed guys like David, it's just a quick step for any back to break into the secondary. A speed line would be great as long as the LBs are oversized but the Huskers appear to have a D-line and a linebacking group both built for speed and not for run stuffing. Once the other team gets the run established, then they start picking apart the defensive backfield.
A couple of the DB's are too slow to cover real good ends. When some serious receivers show up, it'll be Cover 2 all the way and that's going to make a long day for the D-line and the backers.
I saw a lot of one-dimensional offensive work. Martinez left...Martinez right...Martinez throws... Use Burkhead like he's meant to be used...as a battering ram to wear down the D-line. He should be the featured back of the offense to take some pressure off the QB instead of sitting out there like an afterthought.
Check down to the TE more. They were open all night...
With some experience, a change of personel or two and firing Barney and getting a real line coach, this team should be okay.