One very underutilised back exercise is a shrug variation. They're often called Scapula Shrugs and are restricted to rehab/prehab but the poundage potential is massive for an exercise like this, far more than what could be used in the equivalent Row.
Going by quite a few names, Rearward Shrugs, Scapula Shrugs or Kelso Shrugs (after Paul Kelso who popularised them). They are concentrated upper back work without the limitations of using the arms.
If interested Kelso has an entire book in which he gives some practical uses for a variety of different shrugs to help things like the Bench, Squat, Dead and olympic variations.
A video example of Kelso Shrug done on a Chest Supported Row machine: