We're long enough into the format that there's no need for much introduction. Let's just jump straight into it!
Pack 1, Pick 1
To start off, I am going to disregard Weldfast Engineer. Sure, it's a very solid card. I mean, who wouldn't want to play a Nessian Courser with upside? But I don't want to splash it, and it isn't game-breakingly powerful, so I would first-pick plenty of mono-colored commons over the card, one of which happens to be in the pack.
Shock is a great card for Limited. It's efficient removal that rewards you for sculpting a long-term gameplan. Discerning whether or not you can maneuver the next turns such that a Shock to the face ends the game and hence not killing an opposing creature with it is a good skill to have. Overall, the first Shock is great and the second is even better! I'm not necessarily happy to first-pick it, but I don't really mind.
Then we have Felidar Guardian. Can this revolting Cat dethrone Shock from our first pick? The pick is close, and I'm going to argue yes. Although white is regarded as the worst color and revolt is not a good mechanic to build around, Felidar Guardian always seems to do more than I expect. The 1/4 body is good in a format where four-power creatures are few and far between, there are plenty of enters-the-battlefield effects to abuse, and it even saves your creatures from Caught in the Brights, Ice Over, and plenty of other enchantment-based removal.
Pack 1, Pick 4
The Picks So Far:
Third-picking Implement of Malice is definitely not a great feeling. The pack was quite bad, so I opted to take a black card to go with my most powerful card: Gifted Aetherborn. Additionally, as W/B really wants to enable revolt in order to optimize cards like Vengeful Rebel, Deadeye Harpooner, and Hidden Stockpile, the Implement goes reasonably well with the Felidar Guardian. In no way am I committed to W/B at this time, so it's important when considering this pack not to go in with blinders on.
U/B is my favorite color combination in Aether Revolt, so Tezzeret's Touch is pretty enticing and goes very well with the Implement of Malice I just picked up. The ceiling on Tezzeret's Touch is incredibly high, but it isn't such an insane card. With Decommission, and plenty of other Naturalize effects in the set, Tezzeret's Touch opens you up for getting two-for-oned. I definitely like the card, and if I were already in U/B I would definitely take it, but I'm unsure if I want to commit here.
The only card fighting against Tezzeret's Touch is Renegade Map. Man, has this card skyrocketed in my pick order! I've mentioned it before, and I'll mention it again: mana consistency is very important in Limited. With Gifted Aetherborn as a two-drop with heavy black mana requirements, Renegade Map can do a lot to help me cast it on turn 2. The map also helps turn on revolt if I end up in W/B, and it even keeps me open to read the signals for the next couple of picks.
I am going to take Renegade Map. You see, if I end up in U/B, I'll definitely be happy I have the Map, and although Tezzeret's Touch is better and passing the Touch can potentially put another drafter in U/B, the upside of staying open more than balances that out.