Jim Lee's costume features the infamous "midriff window", and is slammed in a recent post. And understandably so, Huntress is a normal woman with no special protection against weapons, it's foolish to leave a gap in protection like that. This costume, with the V neck, is not much better. Whether the bad guys aim for the navel or for the cleavage, it's still bad news if one of them lands a hit on her exposed flesh.
That's why I prefer the modern full-body suit for her, under the presumption it's armored. I'm also in favor of armor for the rest of the Bat-characters as well, liking Batman's movie look far more than the spandex one.
Other characters who have more exotic means of protection can wear as little as they like, but the "just human" characters need all the help they can get.