We bought my wife a GS500, which was alright. She still dropped it a number of times, but she's not the most coordinated so I think the bike had it coming regardless. Either way we were going to lower it but never got around to it. I think the key is just to get a bike that won't be an issue if it's dropped a couple times. That was easier for me when I was 17 and just started, because I was just happy being on a motorcycle. When you bring someone in around a bunch of people with nice and fast bikes, they're not going to want to show up on a beat up old dual sport.
Had I found one for a good price I would've much rather gotten her a ninja 250, that was also one of my first bikes and I loved it, and even though it doesn't have the same HP, I'm pretty sure the ex250 was just as fast as the gs500 is, and much more managable.
If we get her a nice bike it'll probably just be a 600 with lowering links, unless she eventaully takes to Buells, but I know she likes the sound of an i-4 better. I'll just find some links with a range of adjustment so it's easy to raise back up when I want to abuse it for the day.