I really like Huntress. I like the relationship between her and Batman. She has no connection to him, the only reason they even cross paths is that they happen to live in the same city, but he insists that she has to abide by his his rules and defer to his authority. Her reaction is, naturally, "You don't know me, we only just met, who the hell are you to tell me whatto do?" But at the same time, he's so good at what he does, he's so much everything that she wants to become, that at the same time she actually does want to earn his respect and trust, and she does want to be the model hero in his eyes. And even though he bosses her around because he's a control freak and pretty much tries to boss around everyone in Gortham who's involved in crime, politics, business, and the legal system, he also sees his own anger and the mistakes he made both before he became Batman and in his early career in her, and he wants to save her the pain and struggle he went through and does genuinely care about her well being. Its funny that, pre-crisis, they were father and daughter, but it was only in the post-crisis continuity, where they're not related at all and only met as adults, where they have a very real and very complex and, wether or not either party wants to admit it, loving fatrher/daughter relationship. And in the Batman franchise, a franchise that has found family, building a family out of the people around you who treat you like family as opposed to your blood relatives, as a core theme, I think it actually works a lot better. That's really why Batman and his sidekicks are called the Bat-Family, because they are one. Btaman is the dad, all of the sidekicks, including Huntress, are siblings, each with very different and very real relationships with Bruce and each other, Alfred is the grandfather who cuts his grandkids a lot more slack than their dad does, and Catwoman is dad's overtly sexual grilfriend who buys the kids beer and weed when he's out of town... I guess.
Anyway, I love the Bat-Family as metephore for family, both by blood or by circumstance, and I think Helena fits into that absolutely perfectly.
On her own, I think she's not quite as strong because of how well she fist into the ensemble, but then I don't think Batman is as strong without the League or his supporting cast either. Characters are, in part, defined by how the people around them contrast them. But in any event, by herself she's still great. She's very passionate, has a lot of inner turmoil, a lot of conflicting emotions and desires, but still manages to be someone who, at least from time to time, finds some joy in life. What I love most about her is that everything about her is a contradiction. She loves her parents, her father especially, totally and unconditionally, even though her father was a mobster and was as bad as the villains who she hates. She's devoutly catholic, but she's violent, cynical, and extremely sexual. She gets into fights, theatens and beats criminals, and involved herself in life threatening and morally ambiguous situations to help people and make the world better as The Huntress, but her dayjob is teaching high school history, trying to make the world better by inspiring young people and giving them the tools and opportunity to build a better future.
All in all, she's a fantastic, well balanced character.
As for her costume, I like the costume Jim Lee designed in the sense that I am an avid fan of pornography, but in-story it doesn't make sense and is stupid.