That's actually why I finally went with the quilt and won't go back. I quite easily made an attachment system for my quilt much like the kabatic one and so far, in my living room, works like a champ. I felt soooo constricted in my bag without the ability to curl up and twist around and lay on my side and stomach without my face getting stuck in the hood.
As for where the down goes, I don't think it much matters in terms of a dedicated women's bag vs a mans. I've used both, including once trying a women's pad and found it didn't make that much difference. I think they market it such that we need more loft around our mid section (why?? To protect our lady parts??) but honestly I just want it all over me. And as Doug "cuben underpants" mentioned, the quilt actually allows you to move the down to wherever you need it. Again, a huge plus for anyone.
And if you want to actually invest in a bag or quilt she can use for years, I would probably shy away from a women's model simply because I find them to be shorter than the men's versions. If she's going to be that tall anyway, the women's models will probably end up being too short. Not many 6'+ women out there...