Ripple is a big unknown for most people, so is Bitcoin. Combining them together is like unknown². I don't see how this helps.

Ripple should be able to prove itself in the fiat domain first. In fact its usage should be growing fast with conventional currencies. Then it might be shown to complement Bitcoin.

This brings me to the reason why I can't see myself ever using Ripple: money destroys friendships.

If I need to borrow money, I want that separated from my social life. So I go to the bank and deal with them. If I fail to pay the loan back then it is my problem with my bank. It is dirty washing which I do not need flapping in the faces of my friends. With my friends (people I might theoretically trust with money) I play golf or go fishing. But as soon as money is actually changing hands in the relationship, it is not much fun anymore.

Ripple is probably a killer-app in India and its satellite countries on the subcontinent, as they have Grameen (micro) banking.
http://en.wikipedia.org/wiki/Grameen.

In Western countries people want their financial affairs separate from their social life. I just can't see that changing.