Pack 1, Pick 1
Ravenous Chupacabra is even better in this set than it would be in most. A 2/2 body trades with relevant creatures, and there are multiple common Raise Dead effects. And the fact of the matter is that Chupacabra will pretty much always be brutal for your opponent. This isn't always going to be the case about Tendershoot Dryad.
Tendershoot Dryad can completely take over the game. If it survives for two turns, the game is pretty much over. And as long as they can't kill it at instant speed the turn you play it, Tendershoot Dryad provides some value. You can't really go wrong with either pick; however, I think that Tendershoot Dryad arguably wins more games than Ravenous Chupacabra, and is also splashable. So I'm going to take the rare.
Pack 1, Pick 3
The Picks So Far:
Out of Everdawn Champion, Sun-Crested Pterodon, and Martyr of Dusk, which white card would I take? Martyr of Dusk or Everdawn Champion makes sense for curve consideration since I already have a five-drop; however, I have not been impressed with those cards. Everdawn Champion is hard to cast, and can rarely attack. And Martyr of Dusk is pretty much only good against aggressive decks (or at least that's how it's felt in this format for me). Sun-Crested Pterodon, however, has overperformed and is a very good way to close up the game while preventing your opponent from attacking. Flying and Vigilance is quite the powerful combo.
So if I were to take a white card, it would be Sun-Crested Pterodon. But I really don't want to take a card like this early on. The fact that I currently have a splashable bomb and a splashable removal spell means that Evolving Wilds greatly increases the probability that I get to play those cards. I think that's worth more than Sun-Crested Pterodon (or any of the other cards in this pack for that matter). So I'm going to take Evolving Wilds here.