@Aviast
Thanks for the picture you posted
In a downwind you are at a horizontal distance of approximately 6000 feet from the runway, and vertically about 1000 ft above runway. An observer at the runway will see your aircraft at an elevation of 10 degrees. ( 100 feet height over one NM subtends 1 degree arc)
Which means that the observer on runway should raise his eyesight 10 degrees above horizon to sight you. In the same manner you should see the observer 10 degrees below horizon from your left window.
In order that this 10 degree line of sight to pass through "half wing strut" and pilots eye, the pilot's eye must be at the same level as the glare shield. You can do this small exercise using a protractor and 3 plane view in the manual.
As you maintained that you did these circuits with "Half-wing-strut", the only way to accommodate a comfortable eye hight and the 1.02 NM wide downwind leg is by flying at 1500 AGL instead of normal 1000 AGL.
Usually the half wing strut method gives a width of 3/4 statute miles or 4000 feet approx. While in your case it gave a width of 1 NM, i.e. 6000 ft. Which led me to think there must be something wrong, but still you have managed fairly consistent widths, Is it possible that you were using any landmark other than the runway itself? My primary instructor emphasized that I should be able to do the pattern with reference to the runway, the aircraft and nothing else.
In my opinion safe distance from runway for single engine piston aircrafts is no more than 4 times the pattern height above ground. Then instead of 10 degrees it ought to be 15 degrees elevation.
One of the foremost consideration in designating such relation is the scenario of power loss in pattern. Just from how far can a trainee pilot safely land at airport in case of an emergency? We must take into account, representative glide ratio, adverse winds and low time pilot.
Any one trying to maintain wider than 3/4 sm in SE Piston is a safety hazard. There are several schools especially outside USA which recommend patterns as wide as 1nm to 1.5nm for SE Piston. I have never understood why they do so?