Generally, what she wants is a darning foot. Then, tell her to quilt a couple of smallish quilts (giveaways or holiday stuff). You need that time to accustom yourself to going the right speed. If after she's done several quilts, she should know if she is happy with the results or not. Doing a large quilt can be exhausting, but if you limit it to one hour a day, it is way easier..Way easier. I could quilt without a problem with my old Kenmore. Great stitches. No tensions issues. Then my machine was used without my permission and the tension disks were damaged. I bought a Brother PS1000. Horrible machien for quilting - you are fighting with tension all the time. The back looked horrible, the stitches wouldn't lock correctly. All in all, terrible for quilting, but fine for plain sewing. I have since bought a Bernina and am much happier.
So, my suggestion is that she should quilt a few quilts on her current machine. She may be happy with the results. A new machine with a wider distance between the needle and the motor housing makes quilting easier, but if she is happy with her current machine, she can save towards getting a new machine (all the doo dads are great!). Or not. Up to her.