We used to play with Unearth as well. Although it's very nice with witness, it takes up a valuable slot in the deck. At the moment, I cut it, as I think the biggest issue of the decklists posted in this thread is that it has a lot of situational chaff or uncastable cards. My biggest issue with Unearth is that it doesn't make the deck any less prone to graveyard hate.
I'm still unsure whether or not this card belongs in the deck, but as of right now, I'm playing without it. That said, I am fairly certain that my intuition build is much more competitive than the Gifts Ungiven builds posted in this thread. The three reasons for this statement are:
1) Gifts gets shut down by Gaddock Teeg
2) It is a turn slower than intuition, legacy is in a combo centric meta right now.
3) Gifts Ungiven doesn't win the game upon resolution.
I am still waiting for 2 cards to arrive before I can make a picture of my deck and explain the list. >_< Intuition generally ends the game on turn 3.
If I had to pick a Nic Fit build, it would be:
1) Intuition build
2) Valakut build / Rector Build
3) Gifts Ungiven build
The reason for Valakut over gifts is that, at least, Scapeshift wins on resolution.
I'd like to discuss GSZ / Rector / Gifts / Reanimation targets a bit more.
I've been thinking about a few more fringe GSZ targets that I haven't actually tested, but can imagine are some good:
GSZ
Heartwood Storyteller (Against U/W control. Plow or Terminus will gain you a card.)
Cold-Eyed Selkie (Better splash against Merfolk, still as good against U/W control unless immediately plowed. Sadly, only Lord of Atlantis pumps your Cold-Eyed Selkie.
Master of the Pearl Trident and
Coralhelm Commander don't give +1/+1 to the opposing merfolk.)
Rector
Confiscate Against Omniscience you can steal his Emrakul, Griselbrand or Omniscience after he SnT's. Good to have in your hand when SnT resolves. If he has Karakas in play, you can also steal his Karakas and bounce his creature if he's not SnT'ing Omniscience but Griselbrand/Emrakul.