Hi, L. --
I think it's SO great that you're asking this question. You're on top of it :)! I imagine it's probably not too unusual for kids of this age to not put weight on their legs, but, that said, I definitely think it's something to address, and you're doing just the right thing.
My friend's son would do just what you describe your daughter doing, even well beyond 6 months, and I gently tried to caution them that this was something to address. Flash forward another 12 months, and their little guy was getting around by scooting on his bottom. It was such a fast mode of transportation for him that he actually had to be made to walk, through months of physical therapy and concerted effort on his parents' part to break him of his scooting habit. It was not a fun time for them.
I'd suggested to them much earlier that they get some kind of bouncy seat, like the one we'd used for our daughter, that clamped to the door frame. Their doctor advised that these were too dangerous - I guess they might be, if you didn't actually have molding around your doorframe, but that's another discussion. At any rate, they now make stationary bouncy seats that are suspended inside a rectangular frame, rather than from above, and had I been their pediatrician, I would have INSISTED they get one for him to strengthen his legs and give him the sensation of standing and bearing weight. As I said, though, unfortunately, they prefered to not consider it a problem until he was 18 months old. He ended up not walking until he was nearly 2.
So, my advice for you is #1) don't worry about it too much yet, but #2) do look for one of those "safe" bouncers -- which will let her put more weight on her legs than the exersaucer will require. She may not have the strength yet... maybe try her another week or two more in her exersaucer to start building that strength, and then make her support more of her own weight. She will need time to build up to it, probably.
I hope this suggestion helps! Slow and steady -- there's no rush! Just try to make a tiny bit of progress every week and that's fine -- forward momentum doesn't have to be fast :)!
Good luck,
H.