I started off with a 16, and two weeks grinding on CDP and Bootcamp was when I was able to hit 22's. I've been stuck at 22 and trying to figure out how to get better at it. However, I'm also working on decreasing my time on CDP and trying to force myself to get faster at it as well. So I'm stuck within 20's range for now. It honestly just takes practice. When I started off, it felt like I was never going to improve, but if you practice, practice, practice, you'll get better at it.
I usually study PAT right before I go to bed, so I spend about an hour watching videos for the parts I have trouble with and play with CDP for an hour a day. Although, it feels like angle ranking is hit or miss.. :/