Nah, I don't want a meter or anything, just a bit of conduct written in. Like the "don't make aggressive celebrations towards your opponent", something like "players should use celebrations to purposefully upset or distract opponents".
It's very open to interpretation. Some players may see their celebrations as justified, even if the umpire clearly doesn't see it that way. It will lead to heated argument.
I think leaving it to the umpire is best. But give some leeway. if an umpire feel a player's celebration is too brash, then he will have a word with the player a few times before brandishing a yellow card if repeated. Every umpire is different, thus by giving this leeway, the players will know what kind of celebration this umpire will allow/not allow.
the WD scream is pretty nonsense compared to Marin scream. It looked like they are competing. I think the Korea girls scream are louder than Marin's scream. Marin Scream is just look normal now to me and she screams less. Instead of screaming continuously, they should focus more on points gained.
What is scream to one, is loud shout to another. And then as mentioned in this thread, leave it to the umpires what they consider acceptable and worthy of taking action. The laws are written with unsporting behaviour in mind, and there are also instructions to umpires to inform player about distracting, raising fist toward, and shouting at opponent. Marin was reported to have responded "They know now how I play and how I use this scream. In the past, there have been times when I used it to put pressure on the opponent." - http://bit.ly/2NdSy38
