While we don't know exactly how Hour of Devastation will play out as a Limited format, we can get started by figuring out what cards you want to start with. Identifying a range of cards you'd be happy to first-pick helps guide your drafts, and there are some nice ones here. I'm going to break them down into tiers and talk about what each tier means. Let's jump in!
This tier is the best of the best. These are the cards you take if you see them and aren't in any particular order (because nothing beats them). If you open a foil and have two of these, congrats! Pick the one you like best, probably with an eye toward the single-color cards rather than multicolor ones.
These are cards, mostly rare, that you are happy to first-pick. They give you a strong direction for your draft, and you should be thrilled to open a card from this category. They are in a rough order, though that's less relevant than the group they are in.
These cards are the high-tier commons and uncommons that are above-average first picks. If you start with one of these, you are happy but not overjoyed. They are strong cards, and you will try to play them if you can, but aren't as defining as cards from the above tiers. I don't know if this format can support Nicol Bolas yet, being three colors and seven mana, but I'm determined to find out.
This last tier is composed of cards that I would first-pick, but wouldn't be thrilled about. These are the average cards that you aren't unhappy to take first, and sometimes you will do worse. Solid commons, reasonable uncommons, and a couple situational rares end up here.
This isn't a definitive pick order since the format is still undiscovered, but it should give you a handhold on which cards you'll want to start with and which cards can point you in a good direction. I expect plenty of movement once I dive into the format, but for now, this is where I'd be in my first hour of this new Draft format.