Concerning your first and second points. I like the old Mercury nocks. On some strings the nock will slide up the string when I am deer hunting. For those strings I add a small nocking point above the arrow. When I nock an arrow, I can feel the larger lower nocking point with my thumb and hit arrow between the two very easily, as fast as I can with just one nocking point under the arrow.
Concerning point two, I have only twice in over 50 years of deer hunting have let down a fully drawn arrow. Some people cannot draw on a target that they are very familiar with, hold and let down, they will release. Some like to call it TP, I do not, because most of the time these same individuals have no problem accurately shooting large and small game with extreme accuracy and speed. However, every time I go out, I draw and aim at various tiny objects and let down as my warm up. I have seen in others and also for time myself, where shooting at the same target at the same ranges can create an automatic response release. When that begins it is time to mix things up and go stump shooting and when stump shooting, shoot with direct determination, not to hold and let down, but to say, "I am going to shoot that exact spot and with full determinations, shoot." I like to think about what 'am' going to do when shooting. Constantly practicing what you are 'not' going to do can get the shot process confused, as in saying, "I am 'not' going to shoot. In a few weeks with my new bow, when I see a cottontail or a dove, I am not going look at that at that dove or rabbit and tell myself I am going to draw but not shoot. I am going to, with full determination, shoot.
Good point on sticking with a single bow or at least a single type of bow. Although, I am prone to switch hands when I find a place to park myself when deer hunting. I find the option very convenient and my next bow will also have that feature, of course, the back quiver has to come off when I do that.