Optimal swap routes

[mrgrauel]

What would you like to be added:

Swaps always use the optimal route with the best outcome for the enduser

Why is this needed:

Users don't understand pool ratios and shouldn't have to, but at the moment users who want to buy dUSD with DFI always use the dUSD-DFI pool even with a composite swap. The routing DFI - dUSDC/T - dUSD would be much better at the moment (10-20% difference) for them. I know it would add sell pressure on DFI, but it's unfair for the casual users.

Users complain on social media, because it's not as easy to understand.