The same TE I’ve been shooting for a long time. The only thing I think I may be doing is moving the needle too much causing the soreness.
I still get what i call "bad shots" every now and then. Sometimes you move the needle a bit too much or get close to a nerve.
I stopped shooting quads because i seemed to always get near a nerve or have a good "bleeder". There is a sweet spot at the upper/outer area of the quads, but yeah it makes noise when i push the needle in there because it's been shot a few too many times. I used that spot when i used to shoot 3cc at a time.
Glutes and hips seen to be the easiest to avoid scar tissue, my delts have quite a bit too. Been shooting front delts off and on as well.