I do agree with you in part but as far as haveing a "balanced attack on O". Staunton Rivers single wing during the 2016, 2017 campaigns produced 26 wins,only 40 completed passes, 50.5 points per game, and 490 yards per game. Like you said the pass does keep the defense honest and most of SR's passes resulted for big yardage or touchdowns. Also 2017 Army had a 10 win season with a bowl victory and only 20 completed passes on the year.
IMAO l believe LB has a good offense. It's just there style. What they are going to do is grind you. They play physical football when they run the ball. Eat up as much clock as they can. Play good physical defence and are just looking to get a few stops. Next thing you know the game is over with a very low score. Kinda like UVA basketball . (Couldn't resist) But as you mentioned, you have to be able to pass the with efficiency and that is something they just lacked at times in 2017.
Though as you mentioned all of this years champions did have a balanced offense, the bigger picture is they all were balanced on both sides of the ball (offensive and defensive). Equally as good.
With all that being said I don't believe that it's the type of offense (college/pro style) that your run but its the high degree efficiency that you run it.