As long as it compliments your body and you like it, nothing else matters.
Exemption: If you're wearing a clown outfit and you look hot in it, you would be looking good, but you wouldn't necessarly be attractive in it. There is nothing about a clown suit that has a flirtatious appeal to it.
With the one piece outfit your talking about, it seems more ideal for a short girl. The person I'm picturing it on, it would be attractive in a nightclub environment, but it would need additional accessories to make it hot. The dress alone is not that appealing to me.
That bathing suit in particular though... I don't know. It depends on how it looks on you, cause it could go either way. I think on me it wouldn't look good, but on many other people it would, so it depends on whether or not it flatters you.