Pro-Celtics chants are far better than anti-opponent chants. I hate when people stop "Let's god Celtics" chants to boo the opposing team. Inspiring the home team should be the main goal.
Anti-opponent chants should be used to put the focus on opponents who are playing poorly, like Arenas in the first game of the season. Kobe chants in game 1 served this purpose.
Plus, it is fun to include some anti-opponent cheers. The USA chants are funny, but pretty stupid and embarrassing. What help could that chant possibly be? Is that supposed to bother an opponent? It just reflects poorly on us, making us look like ignorant fools.
I was, on the other hand, a fan of the "Pu***" chant against Atlanta. This was great for calling out players exaggerating fouls to get calls.
"No means no" was a brilliant chant. Clever, and offensive to the opponent, no doubt. I tried to start a "bunnies" chant in game 2 when Kobe started off shooting so poorly, but it didn't catch on. I agree that "Bed wetter" would be a great chant if there were to be a game 6.
The "bull****" chant is way overused, even on good calls. This chant needs to be reserved for actual bad calls. Otherwise, the crowd comes off as a bunch of know-nothing biased homers.