I think this is an engine board as well, but it doesn't win by a large margin, because Embassy and money can work really well, meaning:
An engine strategy with moderate or good luck and good execution should beat the Embassies.
If the engine strategy is less fortunate and/or not executed as well, I'm not surprised if it loses.
Because of the Embassies' raw power, you don't have a lot of margin to screw around, either due to bad luck or bad execution.
I'm wary of the Lookout/Potion-opening; I think a Pawn/Potion opening is just as fine if not better. You might be able to make due without trashing with lots of Pawns and Caravans. Opening Pawn over Lookout can get you to a lucky Butcher on the reshuffle or you can use its +Buy if you happen to draw something like Pwn-Potion-3C or Pwn-3C-E.
So where's the payoff? What do you do when you've drawn your deck? The only virtual money is Grand Market, but it may be a long time before you get to it. Butcher can help you with this by saving the coins when you trash Estate for Pawn for instance.
All in all I think it's doable, but as I said, going for the engine doesn't automatically beat the Embassy player. You have virtually no way to stop him (Scrying Pool shouldn't hurt him that badly) and only Farmlands as a way to deepen the VP pool. Only near flawless execution will do here.
I'm surprised that you bought Gold and Silver, that's a bit of a half hearted commitment. I think you either go with the engine and buy Pawns over Silver and a Butcher over that Gold than trying to do both the engine and some treasures. I mean, the treasures and Embassy are a perfect match, the treasures and a Scrying Pool deck are not.