Pack 1, Pick 1
The first question to ask here is, "if I'm going to take a white card, which card is it?" We have an efficient little beater in Skymarcher Aspirant, a solid removal spell in Luminous Bonds, and a powerful aura in Squire's Devotion. Out of the three, I think I would rather start off my draft with Squire's Devotion for two reasons. First, I've found the card to play out well and win games on its own substantially more than finding myself disadvantaged after the suited creature gets removed. Second, and more importantly, this effect is irreplaceable, while both Luminous Bonds and Skymarcher Aspirant do something not entirely unique.
However, I'm actually going to take Forerunner of the Coalition here. I've been very impressed with all the Forerunners and would be happy first picking any of them. If you get multiples, they can entirely run away with the game, but even outside of that they just bring up the consistency of your deck. And don't get me started if you get a bomb-level card of their tribe!
The Picks So Far:
Pack 1, Pick 4
Spire Winder has impressed me. A 3/4 flier pretty much dominates the game in this format, and ascend is a lot easier to hit than I expected. The only downside of the card is that U/B often gets cluttered in the four-drop slot, and so I don't think I want to pick up Spire Winder this early.
Grasping Scoundrel is an interesting consideration. I started pretty high on this card, and while it still has a place in linear aggressive decks, I'm just not certain that's where I'll end up. Sure, it's a Pirate to go with my two copies of Forerunner of the Coalition, but I've found it best to approach this format without blinders towards a tribe.
Dusk Legion Zealot, in my opinion, is one of the most underrated cards in the set. This card is solid in pretty much every single black deck. Sure, it's not the best in B/R Aggro, but it's actually better than you would think there, especially if you have a Cutlass. The fact of the matter is that the 1/1 body actually can trade in this format. And the fact that it's a cantrip that leaves a permanent for ascend is invaluable in U/B. I'm pretty happy to snap this up here.