This seems to pretty much hit it. The first thing I noticed were the hips rising first. Second were the back rounding and the looking up at the beginning of each rep. Forms not bad but could use a little work. Some remedies that helped me(all things I mentioned were aspects of the lift that I struggled with):
-For the hips: I always do overhead split squats with both feet elevated before any squat or DL session as they really help to open up my hips. I hang in the bottom position for a count or two, tightening my glutes as much as I can as I reach for the ceiling, thinking about lifting from the rib cage. You should really feel the stretch in the hip flexors at that point.
-One thing to think about as you begin the movement up to when the bar reaches the knees is to imagine pushing the floor away from you. This really helped me to maintain a very tight back position and helped my legs to get more involved(hips and shoulders rising at same speed). It's surprising sometimes.
-Do you have mirrors in your gym? They are very hard to avoid but tend to make the lifter want to look up before each rep. I find that tucking my chin towards my neck and looking at the floor about 4 feet in front of me helps to maintain a much sturdier back position.
-Grip strength always helps. Nothing much to recommend, but I really like static holds for grip strength. I would either just do plate holds for duration(mentally exhausting too) or heavy holds with a barbell holding it in the top of a shrug position for as long as possible.
Hope some of this helps. Love the deadlift. The one movement where all you have to say is "Pick that up." Best of lifting.