If I were playing for the win, I'd do Silver/Silver into Mountebanks and money. Spice Merchant might be okay to pick up, but I'm not sure how useful it would be. You can trash the Copper you gain, but not the Curse, so its benefit is going to be fairly limited. I'd skip it, but I'd like a second opinion on Copper trasher + Mountebank in the kingdom. Picking up anything else is too slow: Border Village isn't that good. Nobles aren't that good without another source of +Actions. The junk that comes in from Mountebank is probably far too much to make any sort of engine viable, so a Mountebank-BM plan is best.
Now, if I were playing to see if I could build an interesting deck...
There's no way to trash the Curses here. That's a big strike against an engine plan. However, there is a way to skip those Curses, and that's with Golem. Now, getting that Golem is going to be difficult. But here's how the plan would ideally go. Pick up a Spice Merchant early, and start trashing Coppers. Spice Merchant is also the only source of +Buy, so be careful. Get a Quarry, and use Spice Merchant/Quarry to buy lots of engine pieces. Nobles, Border Villages, a Mountebank or 2, more Spice Merchants and Havens and Conspirators. Get some Golems too. Eventually, your goal is to get a decent number of Golems, play those Golems to play all your actions, then Haven away a couple of Golems. This should guarantee that you can play lots of Golems each turn, and with enough Havens/Golems you can essentially ignore Mountebank's attack. Your opponent's Mountebanks will feed Spice Merchant Copper for +Buy, and will force them to either treat Mountebank as a dead card or give you more fuel.
The problem is that the engine is probably waaaay too slow with Mountebank clogging it up. But it sounds nice.