I don't think there is anything wrong with the current rule. I don't think there is anything wrong with the new rule.
As Gilly has said, the problem is the lack of enforcement from the chief marshal down to the buddy marshal.
If we assume that this lack of enforcement will not change, then all the words in the world are pointless.
I see two choices.
Open up the rule to be as simple as possible.
3 points of contact with the ground (that's foot, foot & knee and the actual dirty wet stuff).
Supporting wrist to be forward of the knee.
For everything else, knock yourself out.
Or, scrap kneelers altogether and have more standers.
Erstwhile also ran