I personally strive for zero damage, while accepting that some damage is implicit even if only by increasing economic development near shore.
The closer you want to get to the reef the better your buoyancy has to be. So either keep a distance or perfect your buoyancy, although not necessary by PADI or other course.
Do not touch any LIVING thing underwater. One or two fingers placed on a carefully selected piece of dead coral just to stabilize, no force, is much better than jojoing and kicking your fins to stay in place. You could do this equally well with gloves and the whole no-gloves rule is imho just because people expect you to be more careful without them. If you ever see parrotfish scraping the corals you also realize that if corals could not handle any mechanical contact they would have long been extinct (not an excuse to be careless, just some perspective).
I don't like diving sticks, assuming you mean the metal pins, as you don't get any tactile feedback and you create a point-pressure unlike a finger with or without glove.
Buddy signals to help each other out of a tricky position sound complicated to me. You really should not get into such situations in the first place.
Tucking away any dangling pieces of equipment is a good point as are most of the others. In the rare cases that I do touch the reef it is virtually always my fin tips. Retracting your legs while stopping finning and using your hands and/or lungs to move away from contact works well.
I also make an effort not to kick up a dust storm when swimming close to sand substrate, but I have no problem touching or even lying on the bottom after ensuring it is "clean sand".