Safety isn't really the logic behind her liking a taller vehicle, its mainly for visibility (or at least perceived visibility).
We test drove a Fit last night. My wife didn't really like it. We also test drove a 2010 Honda CR-V and a 2014 or 15 Mazda CX-5. She liked both, but preferred the CX-5. However, I think she's warming up to the idea of just dealing with the Prius.
Having it paid off is definitely a plus, most anything else would require a loan or many months of saving.