I have never looked at a pic of a man and thought he's up for it - as like most men, he probably is
And most women are on a dating site to meet a partner - one nighter or marriage, we want to have sex with the person we meet eventually, so technically anyone on a dating site is up for it. What we aren't on there for is to be abused no matter what the pic is showing. There is no such thing as a type of woman - some women are free with intercourse and some not so much - one isn't good and the other isn't bad
I personally like a torso pic as I like my men to be muscular, lack of shirt is not saying to me 'I like to fuck and run'