AAAAAAAAAARRRRRRGGGGGGGHHHHHH!
In all seriousness, the term "sexist" is bandied about far too much for my personal comfort.
Also, I'm all for females in games being treated equally. I'm all for them being treated equally in the real world too.
With that said, until the day where we all become an androgynous mass of grey skinned Slender Man-esque figures there will be one sort of inequality or another. True equality isn't going to happen in our or our children's lifetimes. The best we can hope for is a society where we're as equal as humanly possible.
As for the OP: I enjoy the outfits. They're quite nice to look at. I don't, however, lose respect for women every time Ivy shakes her ass at the camera. There are other characters in the SC line-up, female mind, that are much more conservatively dressed and equally badass when flinging their male compatriots across the ring via whirling blades/blunt objects/fists of death.
I've certainly seen guys in games behave like total idiots when a female enters the game...I was guilty of that myself when I was in my early teens. I'd like to chalk that up to hormones and the result of limited experience with the opposite gender, particularly in my chosen field of time wasting. That was over a decade ago though and I do believe it's gotten much better as time has gone by.
The console crowd is pretty notorious for its verbal abuse during games. It's not limited to women. Never has been. Never will be. The sheer amount of times I've heard the words "fucking ******" while playing Halo stand as testament to this fact. This doesn't make it "ok" or excuse the behavior, but it's worth taking a moment to fully understand the implications.
You're getting harassed because you're a girl. I'm getting harassed because I killed the guy four times in a row. The point is the harassment. The point is to be an absolute cock to someone else while you're in a position of relative safety and are free from any tangible acts of reprisal. It happens. A lot. Welcome to the internet.
As for Gamer Girls in general? The more the fucking merrier! I don't know of and haven't heard about ANY male past puberty who doesn't want more women involved in the hobby. Men happen to be very fond of women, after all. Hell, my ideal girl is a gamer girl. Anybody who understands and supports that I want to spend a significant portion of my time in front of a computer or TV without treating me like a child is definitely worthy of my respect.