In 2013, Iowa' top 2 sackers were LBs Morris (7) and Kirksey (2.5). Their 3 starting LBs accounted for 11.5 of their 24 sacks (24 was a really low number).
Since that time, Parker has become much more comfortable with changing up personnel groupings, and also more comfortable in man-coverage (those 2 things are related as it is a lot easy to trust your guys in man when you are in nickel or dime peronnel). Iowa probably has 8 legit starting-quality DBs (Moss, Hankins, Merriwether, Koerner, Belton, Roberts, Williams, Harris), and all those but the safeties could be trusted in man.
In short, I think Iowa will show some creativity in getting pressure on QBs. But we might have to win on 1st and 2nd downs to unlock that creativity.