Normally I'd be all about ranking the colorless cards as well, but seeing as how there's all of one common-level colorless card, it might not be all that interesting an article. Sliver Construct is a fine card, though.
Tier 1 - Potential pack one, pick one:
1. Celestial Flare
3. Dawnstrike Paladin
Celestial Flare is one of the stronger pieces of removal in the set, right up there with Doom Blade. I like that it's a very white card in flavor, and I like that it pierces hexproof and indestructible. Pacifism is classic; no discussion necessary. I know I'm going to rate Dawnstrike Paladin higher than most people, but I can't help it. I've always been a fan of vigilance, and after the number of times I've gotten rolled by Mark of the Vampire in M13, I've got a newfound appreciation for lifelink. The cost is high, but spells cost mana, that's how it goes.
Tier 2 - Potential pick one in pack two or three, after my colors are established:
4. Charging Griffin
5. Master of Diversion
Charging Griffin is fine, works really well if you have some defenses back to cover. Master of Diversion is a 2/2 body with a useful effect. Same goes for Auramancer. The set seems to almost demand that you play at least a couple of enchantments, so I'd expect that you're getting full value out of Auramancer around 40% of the time.
Tier 3 - Solid cards to fill out the color:
7. Sentinel Sliver
8. Suntail Hawk
9. Divine Favor
10. Hive Stirrings
11. Solemn Offering
12. Capashen Knight
13. Pay No Heed
I like Sentinel Sliver a lot, but vigilance on a 2/2 doesn't do a ton; by the time you can attack with a 2/2, it's usually at risk of being traded for another 2/2, which means half the time your Sentinel Sliver is just another Silvercoat Lion. In a slivers deck, obviously it's more useful. Suntail is fine, a one mana flyer in an enchantment-heavy set should be useful. Divine Favor isn't a phenomenal, but it makes any creature a problem to deal with. Hive Stirrings I'm rating a little higher than I might normally rate a sorcery-speed token spell, simply because the set favors slivers. Solemn Offering is going to be a damn useful card in this set, I promise. I initially had nothing positive to say about Capashen Knight, but really, it's a two-drop that you don't hate pulling in turn 8, so that has value. Pay No Heed seems just okay, but it can unmake a lot of red decks' plans, and also has a narrow fog effect.
Tier 4 - Not exciting, but playable cards in color:
14. Show of Valor
16. Siege Mastadon
17. Pillarfield Ox
Show of Valor was a deck-filler at best in M13; I expect it to be the same in M14. Fortify is a tough card to judge, but I could see it moving up my list a bit as we see more of the set. Siege Mastadon and Pillarfield Ox are cards, but that's all they are.
Tier 5 - Cards I'd have a hard time seeing myself play:
18. Griffin Sentinel
19. Angelic Wall
Griffin Sentinel has to exist, but I don't ever want to play it. Getting just one power on a three-drop creature never feels good. Angelic Wall is what it is; Fog Bank is infinitely better. Soulmender might fit into lifegain decks, but until I see him getting work done, I'm wary of any 1/1 without evasion.