There are also other ways to re-trigger Gray Merchant that arent permanents (and as such dont add to your devotion)
Since you wont necessarily know when that opportunity will arise, leaving a large amount of mana available every turn might not be practical
And the double creature type means that Bonehoard Dracosaur can slot into a dragon deck, too
Howling Mine / Font of Mythos / Temple Bell In casual places, we also saw Howling Mine making a hit, followed later by cards like, Font of Mythos and even Temple Bell
Going into Portland, I knew Archies had an extremely poor performance the weekend prior and poor matchups vs
Later, you can sacrifice them for Goblin spells like Siege-Gang Commander, make them legitimate threats with Goblin Trashmaster or Goblin Warchief, or turn them into mana with Nothing like ramp in a red deck