Rubio may not punch as accurately or skillfully as cotto, but he hits harder and he came in at 180lbs. No respect will be shown for a tiny 5'7 middleweight like cotto.
I don't think he will respect Miguel because of his power, more his skills, achievements and everything combined. GGG doesn't always come rampaging in looking for the kill. He is a smart, skillfull boxer and I think he would try to show that against someone like Cotto. I think he would feel him out for a couple of rounds and steadily step up the pressure and intensity until Cotto wilts.
Well your right about GGG's style, he isnt a wildman. But this wont last long at all another fight where GGG may look to showcase his skills but end up putting cotto asleep with a left hook or right hand. Or stopping cotto on a brutal rib breaker. Murray should show more resistance in the february bout then cotto will, being a big middleweight with a decent defence.