5-player game.
Kingdom: Pearl Diver (bane), Native Village, Fortune Teller, Smugglers, Cutpurse, Sea Hag, Young Witch, Caravan, Farming Village, Horn of Plenty, Harvest.
How do you start 4/3?
Young Witch/Silver looks like a natural opening, with the expectation that you will have curses and estates to discard, so the Young Witch discard won't hurt much, while nobody will be buying Pearl Divers. In our group, nobody tried a Sea Hag, but the other 4/3 players opened with Cutpurse or Caravan rather than either curser.
And, for that matter, how do you start 5/2? Horn of Plenty to get Native Villages (or Pearl Divers if a lot of Young Witches are around) early, followed by better cards later, looks like a good choice. On the other hand, Harvest will cycle your deck, and will make use of the curses.