one thing Ive been trying is just to put a ball on the table , anywhere near the middle and my cue ball in line with the object ball and pocket, then try to sink the ball with a straight shot, and follow it in with the CB. A scratch in normal play but harder than one may think to actually do! I think that to do that on any consistent basis requires a good straight stroke., which I'm still striving towards.. any offset of the stroke pattern and both balls will not sink, it also shows a bit about top or bottom as it affects how closely it follows or if it stops or catches up to the other ball.
the other one that's harder than I thought, is to actually stop and freeze the ball, I find it much easier, if I accept some variation ,but much harder to actually freeze it right at the point of impact without it bouncing to the right or left, or forward of back at least a little. for some reason I'm prone to really making a ball to try to plant it in place, why the harder stroke seems to be required , or why it helps I can't understand. It seems common to do that when you have a duck right over a corner pocket, but it's not really necessary to smack a ball hard to make it stop. It might just be because that way I wont loose the backspin spin due to traction across the table which I can avoid completely with a harder shot.
maybe I need to discover how softly I can hit a ball, and stop it with varying distance.. because if it's a longer distance I need a certain amount of bottom, but distance between OB and CB affects all that.. Finding that threshold may help me make more successful hooks. with improved control I can hit a ball and control where the cue ball stops and doing that well gives a great advantage. Often I'm attempting to go stick to some other nearby ball, but any slight failure and it's usually not resulting in a hook but just a rather dumb looking shot..