I'm not saying I'm some big expert (far from it), but I do know a few things and one that I wish I'd believed when I was newer was not to microanalyze.
Unless you have a HUGE back, or your definition is phenomenal, it's hard to know if your "middle back" is lacking. Soreness doesn't mean a goddamn thing. As for stronger, how the hell would you know something like that? You can't isolate your rhomboids.
My point is that, really, for 99% of us there's no need to comb through magazines and try to concoct these elaborate routines to target different areas of different muscles. I keep hearing kids (not calling anyone here a kid!) asking how to improve their rear delts, or the sweep of their quads, or the horseshoe of the triceps, when the problem is that the entire LIMBS are small.
By all means, switch things up if you want, I do it all the time, but trying to target such overly specific areas is unnecessary unless you're a pro bodybuilder. The middle of your back should be doing PLENTY in ANY row. T-bar, cable, dumbbell (one or two armed), barbell, underhand, overhand, chest-supported, free standing.