I hadn't heard "Rethuglican" before. I'd go with offensive on that one. McSame, while a put down, does have some legitimate rhetorical flourish to it. Possibly I feel that way because I'd say pretty much the same about the long forms you give. "Republicans are thugs" is offensive and useless. "...policies are identical..." is a reasonable argumentation tact.

It probably does me no good, but I try to be meticulous in typing, oh let's say, "President Bush" even when I'm thinking "*(&%^%*#$". Well it does some good, it lets me believe I'm taking the moral high ground. At least not dragging in the gutter anyway.