For cryptocurrency to cryptocurrency, we can already send any amount directly to anybody anywhere instantly.
That's not a use case Ripple is intended to facilitate. You can of course choose to make direct XRP payments, just as with any other cryptocurrency.
For Fiat currency, even with the use of Ripple, you will still need to use the banking system to move the money to the end point. You can't magically move US$100K from one place to another. Someone will still need to absorb the banking fee for the transfer.
The fee for the netted payments to be exact. Fees at gateways are on the order of 1%, not the 15% fee Western Union charges.
So why even create a complex system when it doesn't improve things at all?
Remittances and buying selling cryptocurrencies against fiat currencies are the killer applications right now.