My favorite of the ideas I've heard you discuss is reversible credit-card-like txs. I think giving bitcoin this ability will make it a lot more friendly to non-bitcoiners.

For an early product though, I'd focus on the places where fiat absolutely sucks at doing its job and so much so even non-bitcoiners would use a fledgling bitcoin escrow startup to solve their problems. That's the "disruption" I'd be seeking at least.