On the ghr's get the pad at least mid-thigh. The closer you get it to the knees the more ham strength will be needed. Just like when you did it wihout the machine that is sometimes called "russian leg curls" although I don't know where that came from
. Just remember that these machines are meant to be able to do more than one thing so you have to set up correctly to emphasize whatever you are trying to emphasize.
There is nothing wrong, exactly, with what you were doing. It's only that taking an unchallenging exercise and adding weight is silly when you could increase the challenge much more by adjusting the positioning. The closer you get it to the knees the less you will be able to do the hyper at the beginning. You will need assistance to push off. The torso must remain straight during the knee extension portion of it. There is nothing wrong with doing the hyper first it's only that the closer you get the pad to your knees the more assistance you will need to get moving and if you start in a low hyper position you will have a hard time getting up.
You can also contunue to do a version of the exercise more like the way you did it there but concentrate on activating the glutes and make it a hip extension exercise, not a hyper.
I've seen people using those machines going up and down like a piston about a hundred times. It's just too easy. What's the point when a 12 year old girl can do it 15 times? You'd be better off doing pullthroughs or Romanians in that case.
On the rows I've explained it plenty of times so let's see what happens.