Not a woman but...all the climbing specific knives I've seen are not very function everyday knives, whereas any pocketknife with a retention clip can be a functional climbing knife.
CRKT, Benchmade & Kershaw make solid tools. 6.5 - 7.5 inches is probably good. Just remember the difference between male and female hand sizes. Just because it feels good in yours, doesn't mean it will feel good in hers.