Interested / shocked to find it a term of endearment in some parts.
Personally would not use it, though sometimes I'd switch from twit to twat if someone had been a massive nuisance... I am unhappy hearing it spoken by a man, especially if in earshot of any woman.
However, to find it used by women is worse, in my view, and fairly rare (except on MN, when it is so often unnecessary - someone writing about "cunting Sainsburys" just baffles me).
"so many words for their penis they never have any ambiguity as to what they are referring to or potential vulgarity associated"
Well, cock, dick or prick are often used and (from man to man, at least) usually as an insult.
"it seems that the female ones are consistently felt to be 'worse'"
I suppose that comes partly down to context.
I'd have thought that "bitch" and "cow" were still more commonly used by men when insulting women, while using "cunt" and "pussy" (along with prick, cocksucker, motherfucker and knobhead etc) for insulting men.
I remember speaking to someone at an estate agents and in the background two (young?) women were discussing someone. Quite surprised me to hear one call him a "dickhead" (was about 20 years ago, when teenagers probably didn't swear quite as much, and TV shows carried less swearing, I assume).
Incidentally, has "pussy" lost its place as an insult ? Seems to be used more on TV and comparable in its "acceptance" (in terms of inclusion by a channel) as if someone was saying something as innocent as "wimp".
It seems to me that male or female terms are used to insult men, where there's not quite the same parallel for women, or am I just living a sheltered life ? (Maybe I should do a pub crawl some Friday and Saturday nights to find out what 20-somethings say about each other.)