So if you get urge to rock and do something else instead, that just doesn't help? Whatever you do.
No, it definitely wouldn’t help. I’ve never had any other stims aside from rocking, and there’s no way to substitute or modify it.
I find only subtle changes to be possible. I switched from pulling on my fingers to pulling on a stretchy noodle, and I switched from biting my nails to chewing on my thumb. But changing to an entirely new thing would be more difficult.
Your modifications make sense to me, because you didn’t actually change the stims themselves at all; you just changed what you pluck at with your fingers or chew on with your mouth.