We could always learn a lesson from history, and create a 'Fever Code', using a vocabulary that only those in the know are aware of. This way, we don't offend/alienate the families, pack out the Ring of Fire, and still abuse the opposition/fans/officials to our hearts content.
Thanks to Cosimo, we already have the term 'possum thrower' to describe what the officials do that has afflicted them with near-blindness. As in, "The referee's a possum thrower'.
'You're so f***ing sh*t it's unbelievable" is easily made less offensive, but no less meaningful, by changing it to "You're so Payning Kruse it's unbelievable". If we want to give this one more of a Wellington flavour, how about "You're so G**-ing Elrich it's unbelievable". As you can see this one is quickly catching on, as demonstrated by the presence of asterisks (**) already.
Unfortunately, my final suggestion, however, cannot be Phoenix-ised, as there is no insult worse than "You're a Musc*t" (The Tard of course)
Happy chanting.