The offense will be very comparable to last year in quality. The tight ends will be greatly missed, but I think the Smiths both take a step up, and Tracy gives a few more big plays than Easley, if not the reliable security blanket. Running back will be greatly improved, if only by having a solid Sargent in place from the start of the year. The tight ends will block, and occasionally break a big play. A consistent and injury-free Stanley is the biggest key.
And, the defense will likely be substantially better. Teams will need to scheme specifically against those DE's, comparable to teams being forced to scheme against the TE's last year. Double teams will take resources from the opposing offenses and leave the tackles and linebackers to make plays, There will be few big plays around either edge, or on long developing pass plays.
Losing Hooker will be the biggest hit on the defense, but I think OJ does have the physicality and cover skills for the CASH. Brents and Hankins on the outside may be the best tandem of island-quality cover corners in the KF era. Iowa has almost always had one elite cover guy, but seldom two on the field simultaneously.
And Special Teams will be improved. Punting consistently. A feared kick-off returner. Recinos will be a tough replace, but at least Duncan has hit big kicks.
Overall...it will be an improved team. I hate to think how it good it might have been if the Juniors had all stayed.