It depends on so many variables - trhe individual, the design and the tattoo(s) are all so very different, that i can love them on some, and hate them on others.
As a music writer, I mix with tattooed people a lot, and i see some wonderful artwork that looks spectacularly good on the recipient, and some rather ill-advised ones as well - just like life in general really.
i remember the first time i saw what is now referred to as a 'tramps stamp - a design on a girl's cocyx which i saw on a gorgeous holiday rep in Spain about ten years ago - they were nothing like as common then. When she bent over to pick up her drink off a low table, her tee-shirt rode up a little, and there was this delicate Chinese symbol, followed by her goldren brown skin, i thought it was wonderully erotic - but have seen dozens since that are anything but.
I personally would look ludicrous with one - but i have no objection to other people - but then again, i rarely to object to anyting other people choose to do to adorn themsevles.