Here's the way I break down this coming season:
The cons first:
Team was 5-7 regular season last year and returns a lot of the same players
Team loses 2 dependable interior d-linemen to the NFL
Team loses a difference maker at fullback to the NFL
Offensive line was serviceable and lost a couple players to graduation
QB position is so important and Nebraska's QB was the definition of inconsistency resulting in 16 interceptions which undoubtedly led directly to some losses
Nebraska defense was nearly laughable at times last season, particularly against the pass
The pros:
The same QB is now a senior and in the second year with real offensive/QB coaches. The upside is there for a breakout season
Several of the 7 losses were downright gut punch losses where the games could have gone the other way. Flip a couple tough break losses to wins and you're talking about 7-5 vs. 5-7.
The defensive backfield looks to improve dramatically after a season under their belt and some playmakers who are a year older - if they can mask the D-line in the early part of the season, the defense should make a major leap this year
The wide receivers may be the class of the B1G
The running back spot may not have one elite runner, but they are deep and can afford injury should the bug bite them
Special teams should be salty at punter, FG kicker, and punt returner
It's usually hard to see a team make a 3 game improvement when you have most of the same characters, but in this case, I think there are circumstances that should work in the Huskers' favor. I've seen Vegas' line of season wins for Nebraska at 8.5, the same as Iowa's. To go from 5 wins to 9 wins (regular season only) is a pretty dramatic leap that should normally beg gamblers to take the under, but I think they sneak over and win 9 games this season - which will certainly make the season a little more palatable than last year.