I was just looking down the road a bit. I'm still on ground rows (step 4, 4x9).
Elevated ground rows seem more challenging in a very obvious way.
But the Bulgarian rows, with the limited range of motion, actually seem easier than the elevated ground row to me. It looks easier to stop at that 90 degree angle than to pull all the way through the ROM and have the hands at the armpits.
Curious to know what I"m missing. Obviously largely an academic question for me at this point.