In my experience, it's all about throttle (trailing edge / back line tension) and rotational control.
First major building block to advanced control with a Rev is more or less owning a hover in each of 12 (or more) clock positions...
Don't try to make it stay perfectly still, give yourself a "wandering" range of a couple feet and work to say in or close to that.
Focus primarily on the angle of the leading edge (facing correct clock position), break it down, see the angles, take mental pictures.
If you're facing 3 o-clock, slowly turn to face 4 o-clock and hold the hover there for 10-15 seconds, maybe more, before shifting.
At each of the 12 clock positions, at the moment you have a semi-decent hover, take a mental snapshot of how your hands, body, feet and head feel, try to store some of the "body set" for each position, so you can settle into each in turn as you rotate through the clock positions.
Don't worry about "clockwork" (snapping), just shift the orientation smoothly and slowly, focusing on your ability to choose any orientation, rotate to it, hover there, choose another, and so on.
I think really, the other thing that takes work is finding the hand position that allows you to drive the Rev at one speed, without the oscillation between forward and brake... Figure eights, circles, squares, diamonds, all good shapes to practice this - and feel free to push the edge, feeling how much finesse it takes to keep an even speed - not unlike a dual line.
Some of my favorite, regular drills that I do for both fun and practice (works great with a funky beat)...
Off the ground pass, at one consistent speed through the turns: diamonds, octagons, squares, etc.
Always, always trying to land either with both tips at the same time, or flat on the 45 edge, no bounce.
Hop, bicycle rotate, land on both tips.
Hop, clockwork rotation, land on both tips.
If you look hard at my Rev flying, you'll see it's really not extremely different than my dual line flying... That's my dirty little secret, is that I fly Revs like dual lines (with regard to sail loading, modified combo turns and landings) - the same moves feel good, Rev is more complex, but the dual lines give more "krakow!" in the movements.