1: this is the weirdest limited format ever
2: creatures are MUCH bigger than we're used to at all rarities
3: removal, even shitty 6-drop removal, is at a premium. This is likely to try to speed up what would otherwise be a slower format than m14.
4: black has better removal than most colors, it seems, but except for Pharika's Cure it's all insanely expensive
5: agent of the fates should've been mythic for limited purposes. I cannot think of a card I would pick over it in this set, with all the inexpensive cantripping enchantments and good commons with Bestow
6: the common 'bestow' cycle are almost all first picks, the sheer value you get out of making a creature huge -- especially in a format almost entirely devoid of conditionless removal -- is obscene
7: the format is -probably- slow enough for stuff like slip of hemlock to be taken higher than it normally would, but it won't exactly be good. "Kill your 6/6 flier that's already got me nearly dead, you get a 2/2 flier back anyway" will not feel great.
8: bestow is an amazing mechanic in limited, and we have access to a ton of it. This is going to be a swingy-ass format, and there are TONS of combat tricks so it's impossible to know when it's safe to attack. Memorize them.
9: pick black or white at the prerelease, none of the other promos do anything relevant enough and black looks like it'll be pretty decent anyway
10: bounce is probably pretty good, considering how fantastic Bestow is. W/U tempo could be an archtype, so picking white and hoping to splash blue bounce spells to prevent your opponent from "going big" is legit.
11: sea god's revenge is the new Into the Void -- it's overcosted because the effect is nuts in such a swingy limited format. You want one in your sealed pool to top off your curve, but don't load up on them
12: 18 land decks are probably correct more often than not
13: defensive heroic abilities -- like wavecrash triton and agent of fates -- seem better than their offensive counterparts right now.
14: flying seems to have limited coverage across the colors, a lot of decks are going to be focusing on getting one or two massive bestowed creatures out. Blue can use Griptide, etc, to hold that creature back while swinging in with small fliers. Vaporkin.dec will be fun.
15: Pick heroic enablers up in the latter half of a pack if you want to go big with that mechanic, likely in W/r. The mechanic is narrow enough in offensive white (mostly in uncommons/rares) that I don't know how consistent this will be.