I use a very steep throttle curve in my radio, for one. This helps with good throttle response in terms of retaining altitude on recovery. Most of the time I do let it drop a bit, though, unless I flip close to the ground. Makes the recovery smoother. My throttle curve is set as a linear curve and from 75% and upward throttle on the stick, the output is set to 100%. Essentially, the top 3 points on the curve are set to 100% and my low point is set to 0% and everything in between is inhibited to create a linear curve.
As for stick movement, the idea is to reduce throttle when inverted unless you do large loops with lots of altitude during which holding the throttle constant works fine, but even then, reducing throttle a bit when inverted gives you better control.
As for quick flips, reducing the throttle when inverted is key, especially when flipping close to the ground. Higher flip rate programmed in the flight controller helps, of course, but throttle management can really make a difference between a fast flip and a not so fast flip. For example, if you reduce the throttle at the same time as you initiate the flip, the quad will flip much slower, whereas if you let the quad go through 25 or 30% of the flip before reducing the throttle, then it will flip much faster. Bottom line is if the props turn faster under higher throttle output when initiating the flip, the quad flips faster but you still have to reduce throttle when inverted or else you lose too much altitude and control. The same goes with giving it a bit of a throttle punch when initiating the flip. This simply helps propel the quad into it's flipping rotation.
If you saw my thumb on the throttle stick when doing back to back flips and rolls, all you would see of my thumb on the throttle stick is an up and down, and up and down motion.
You know, Warthox actually has videos where he shows the sticks as a separate layer. You should look them up on Vimeo with the search terms "Warthox Flight School." That guys is an amazing pilot. Weird thing is, he doesn't use colored props or any kind of orientation markings, yet, he rarely loses orientation. He always seem to know which way is which.
Don't hesitate to post more questions if they come to mind.