Pictures don't look that bad to me.
I've been working some clear-cut land with disc harrows and a landscape rake. Not perfect but good enough.
In my case I have dug the stumps out.
I wish I had a tiller.
Doesn't seem like a tiller would be happy in ground stumps.
From a distance our land looks beautiful, but don't try and run on it, or you'll end up with a broken ankle. I have some holes that are more than a foot deep and impossible to see until the tractor is dipping to the side. Mowing it is not fun.
I love the tiller so far. Gets things nice and fluffy. Fortunately there's been enough time between the stump grinding and present day that everything has rotted. I wouldn't try it if the stumps were oak or some other hardwood.