With Pro Tour Rivals of Ixalan coming this weekend, I'm excited to see what the different teams have figured out about this format. I'm currently of the opinion that, while aggressive decks exist and can be good, you're better off trying to build a more midrange or control deck. Blue decks can certainly be tempo-oriented, but almost all of them will still put Sailor of Means to good use.
In fact, an interesting observation I've had about this format is that it seems like only a small portion of either player's deck matters in any game. What I mean by this is that each player is playing cards, such as Sailor of Means, that invalidate some percentage of their opponent's deck. Aggressive decks may not be performing well because they aren't as good at executing this kind of strategy and their linear approach is easier to take apart. This is also why flying creatures are performing so well, as the ground gums up and then only flying matters. So when playing a game of Rivals of Ixalan Limited, make sure to ask yourself what matters and save your removal spells for those creatures.
Pack 1, Pick 1
Both Squire's Devotion and Reaver Ambush are cards I'm happy to first-pick, but they don't surpass the other options. I will say that I think Devotion and Ambush are actually close. I currently have Devotion as the third best common, just behind Moment of Craving and Kitesail Corsair (no, Bombard is not in the top three, it's fourth), and I also have Craving and Corsair above Reaver Ambush. I think if I had to choose between Reaver Ambush and Squire's Devotion, I would lean Ambush, but it's close.
Dire Fleet Daredevil is a solid card. It's great in every red deck, whether aggressive or not, and it's great in the early-game and the late-game. You can't ask much more from a two-drop. But all in all, it's just a solid card, not a bomb or anything. And I'm of the opinion that the last option is in fact a bomb.
Golden Demise is an absolute beating. This format is chock-full of 2/2s and battlefield stalls happen quite a bit. Having access to Golden Demise as a game-ending effect in a large portion of matchups is nothing to scoff at. And thanks to ascend, you can even include this in decks with a bunch of 2/2s as well. I'm always happy to first-pick this card, and you should be too. I frequently see this card passed, and I believe that, more likely than not, that's incorrect.
Pack 1, Pick 3
The Picks So Far:
Hunt the Weak is a solid card, but I haven't liked B/G that much in this format so far. And while I'm not locked into black, I think both of my black cards are better than Hunt the Weak, so I don't think I can justify taking the fight spell.
Skymarcher Aspirant is a solid little one-drop. I wouldn't fault anybody for taking it here, using the tiebreaker that they could end up in quite the solid W/B Vampires deck; however, I consider this card not as impactful as the other option. While it's an efficient beater that scales well with the game, one toughness is a liability in this format to some extent, and I want to pick my second color based on a card with a higher ceiling.
Speaking of a high ceiling, Forerunner of the Empire continues to overperform. There are plenty of one-toughness creatures that this card can pick off, but there are also abundant combos that go well with the Forerunner, making it a great pickup. Needletooth Raptor is the most obvious, but Raptor Hatchling, Crested Herdcaller, and Raging Swordtooth all mimic a Pyroclasm. And if you can tell from what I said about Golden Demise, that's a great way to win in this format. I'll happily speculate on Forerunner of the Empire here.