Heres what it looks like when I put the Adventure Dragon on the curve based on the Adventure mana, and each Dragon on the curve based on the eminence mana discount: Ah, thats much more like it, dont you think
You'll do fine you happen to run well and hit some of the high-end mythics or chase rares, but the typical box of Theros: Beyond Death will very likely contain less value than the expected value suggests
Creature - Angel Spirit Timeless Witness When this creature enters, return target card from your graveyard to your hand
Its still an awful topdeck, but it at least does something even if your opponent has nothing to take, and it could be a big player in U/B proliferate
That said, there are a few interesting choices here to discuss: Crib Swap is a white instant spot removal thats also an eldrazi spell, given that it's a kindred/tribal card