I'm not saying 'avoided,' but if you look at the ScubaPro Hydros back-inflate system, do some searching on here for complaints about the shoulder strap - I don't recall exactly what piece is allegedly prone to tear, but I've read enough people complaining about it that I was put off from being one a few years back.
There is a lot to be said for BP/W, if you're willing to make the choices involved (e.g.: steel, aluminum or 'other' BP material), and you get someone who knows what they're doing to thread the webbing through it (or you're willing to DIY based on watching YouTube videos or some such?). I saw one online vendor who offered to do that for a fee.
If you go with a traditional jacket style BCD, I'd suggest a few basic things:
1.) Get weight-integrated. If she has one and wants to use a weight belt, she can. If she has one that's not, she has to use a weight belt.
2.) Get one with 2 cam bands, not one.
3.) When I used a jacket style BCD, I came to value the rear trim pockets on the back. Yes, you can buy add-on pockets to put on the cam bands, and having pockets built-in to the BCD was nice.
4.) Some Zeagles (at least as of a few years ago when I was looking into it) used a rip cord system for securing and releasing integrated weights. Some people valued that; I didn't like the idea of needing to rethread them, but if you think they sound more secure than plastic clips, it's something to think about.
5.) You may want to at least consider some back inflate options.