I don't see how the two are even comparable. CM Sucks is awful. I don't hate Cena or anything, but it's one of the more cringe worthy things he's come up with.'CM Sucks' is not clever at all and is more or less just an immature corruption of CM Punk's ring name.
'Randal' is more or less Punk talking down to Randy by using his real name in a mocking way.