Funny; I was only discussing this the other week in the pub! We came to the conclusion that the existing words were perfectly sufficient - providing they were prefixed by the word "Ginger".
Anybody can acept being called "A Tosser"; but "A Ginger Tosser" - that's just insulting. The same applies to any other insult that you can think of; insert the word Ginger and it is suddenly more offensive to the recipient, and yet funnier to the cusser.
BTW: My hair is brown!