A. It’s ridiculous to consider a drawn line on the ball to be an “object” as meant in the rules. So no, it shouldn’t be illegal.
B. Draw anything you like, just don’t slow down pace of play with your alignment routine. Hell, I know knuckleheads who spend time aligning their ball on the freaking tee!
C. However you do it, at least mark your ball for identification. Too many still don’t do that...
As we both know, feel ain't real, and descriptions can be tough. I bet we play the shot from the rough pretty similarly, open face, plenty of speed, relatively steep attack. It sounds like maybe our bunker techniques are a bit different.