the straps are pretty stretchy, there a plenty of guys with long torsos too.
Try on some different brands, but overall you'll be looking for the same qualities as you do in regular shorts.
The only feature in bibs that doesn't apply to women is how low the front of the waist is (this is for ease of, er, um, *ahem* guys to pull out the hose without dropping the straps). Typically on the lower end bibs the front waistline comes up to the belly button, but on the 'pro' level the waistline drops down in a V shape nearly to the pubic area.
welcome to bib world you will love it!!