Bah on the standards, make 'em so they are uncluttered and make sure your intent is clear.
THAT said, my OCD kicks in with multiple line notes to the left of center and I am just compelled to use the "force left justification" option and have the leader off the middle of the first line of text. Right justified multi-line text is just unnatural and wrong on every level my eyes can see. All note to the right side are also left justified with the leader again at the middle of the first line. Not a standard but the way I would do it if still on the board and a 30 year old personal preference. I also like the option of dragging the leader arrow point under the note . . . unless there is a choice that makes the intent more clear.