For a different perspective from Arne's, and from watching you shoot, you may be more naturally inclined to shoot with a dead release than with a dynamic release. The main proponent of the dead release today is probably Rick Welch. If you are interested, you can look up some of his videos on YouTube.
What Arne teaches, the dynamic release, is more in the main stream of modern archery instruction. Most of what he told you, such as head position and anchor, is applicable to both the dynamic release and the dead release. However, there are a few things that aren't. One of the things which is applicable to the dynamic release but not to the dead release is to never move your string hand in a forward direction. If you watch videos of Rick Welch, you will see that he occasionally moves his string hand forward as he is settling into anchor.
In the dynamic release, back tension is steadily increased throughout the draw and release. In the dead release, back tension is increased to the point of anchor. Then, as if shifting a transmission from drive into park, the back tension is locked off while the arrow is being held at full draw. It is this locking off that causes the hand to stay more or less in place with the dead release, as opposed to the distinct rearward movement of the hand with the dynamic release. There is a moment with the dead release before locking off the back muscles where adjustments can be made without wrecking the shot, such as a slight forward movement of the string hand. I don't think this is a great idea, as it wastes energy, but at least it doesn't wreck the shot, as it would with the dynamic release. After locking off the back muscles, no more adjustments can be made, and it is as critical in the dead release as it is in the dynamic release that there be no relaxation of the back muscles until after the shot is released.
I think that if we observe champions such as Rick Welch and Rod Jenkins, we have to agree that it is possible to be an excellent shot using either method. My own experience is that it is not possible to shoot well blending the methods. For example, it is not possible for me to shoot well if I stop my draw to hold at full draw, and then try to re-start pulling to complete the shot. I either have to increase back tension continuously throughout the shot, or else lock off my back muscles, hold, and release without any further increase in back tension.
Some food for thought, as it seems to me that you are really trying to shoot with a dead release, but are not quite able to get it.