First thing to help with the unrack, lower the rack height. You shouldn’t need to reach that high to get the bar out.
To think about your arch don’t worry about the set up as that is the best it has ever been. Think about driving your chest to the bar as hard as you can on the way down and driving it up to follow the bar to lock out on the way up.

Great job! Matt’s advice is spot on. I would like to add that a little more leg drive when unracking the bar will also help keep your chest up and help stabilize the bar faster. Keep up the hard work.