I've just been doing firewood and cutting down a bunch of dead firs and pines.. I really have no idea about the size and shape of this mulberry tree (there are none around here)..
Is mulberry wood a brittle or flexible wood? that can make a lot of difference in your cuts as well
For a tree of any significant size, I like making the wedge cut about 2" shy of the centerline of the tree, and my back cut about 2-3" above it.
You don't need to have all that much line pull if you can get the cable up high enough... if the tree is about 60' high as you say, and you can get up about 30 or so, I doubt there are many trees around that would require more than a ton of line pull to get them to fall your way, if they aren't leaning.. if they lean, it can require a lot more.
For the fir trees I was falling, a lot of them were perfectly balanced, and that didn't make them easy to fall, I'd wedge cut a bit over half, then back cut for about an inch of hinge and they'd still stand there perfectly, I'd just push on them to make them fall over... these were about 50' firs, with a 14-16" butt diameter.
2 years ago (nearly to the day actually), I lost one of my friends to a logging accident... he was an experienced faller, but messed up... here's that story
They had a Cat 940 grapple loader against a big dead pine (30" butt diameter, probably about 100' high), and he instructed the loader operator to put his forks around the tree and push on it, he did his cuts, and the hinge broke, the tree came sideways, and since the forks were on each side of the tree, it took the loader with it, and he was crushed by the loader. This was a guy who worked over 20 years in the bush.