Basic high prep can be executed right away without thinking - FH ball? Unit turn and both hands on racquet high prep, then judge the expected contact height and drop the racquet accordingly. Faster ball incoming? Abbreviate and go straighter to behind/below the ball.
Meanwhile the height of the high takeback depends a lot on what kind of bounces you face - your opponent, the surface. On faster court against flattish hitter you want to be compact to hit faster lower incoming ball. On clay against a heavy topspin hitter, or even a moonballer, you can get better results preparing higher.