The issue with rushing for Nebraska is that in terms of raw rushing yards, they did well. But it wasn't a particularly efficient play and they relied on the QB run game to move the ball.
Without the threat of a QB run, which I don't think Nebraska will want to do at all with Dylan, is how much they can get out of the traditional running game. Nebraska has been average to below average doing that.
I think you're correct, they've tried to address these problems by brining in an RB transfer from Oregon, and getting WR transfers from Texas and Wake Forest. They brought in an OL from Florida. They realized that these were problems. The question is if they'll be successful in integrating these players in ways that help the team.
I don't think the coaching staff on offense is particularly good, and I question their ability to both put players in positions to succeed and to call plays that are complimentary to one another and help the team win football games.