Overplanner here, myself. But seeing all the wonderful patches here is helping to loosen me up. I did specific graphic arts for years, and my brain wants to stay in that zone. 90 degrees is supposed to measure a full 90 degrees. No variance, but these are fun, because even though they are squarish...they can kind of get a bit wonky. And you can always pull and twist and spray starch until they fit together.
I think that is the beauty of the patches is that everyone approaches them differently! They are art in themselves. I am a seamstress too and for me it was difficult at first but after a few swaps I have come to realise that perfection isn't the name of the game! As for your back, I also still have issues with a sloppy back and try different things to get a neat appearance, I like your idea of a long tail and weaving it in....I think I'll try that next time.