Out of 23 artifacts, 2 of Genesis are 3 purity, 12 are two purity and 9 are one purity. Of these, 8 are Unique. In theory, you can have anywhere from 12 to 18, and maybe even more artifacts on the field. That would boost Collector to ridiculous 50+/50+ stats at 12 artifacts. As 12 are dual purity, I doubt using Enyah would help your numbers much, but that's 9 1-purity artifacts crammed into a single deck. Using either a triple Genesis or two sets of dual purities that have 2 2-purity artifacts can yield up to 13 different artifacts in an Enyah deck. Although, the Tome will innevitably explode, so that's always something to keep in mind when factoring it into Collector. He seems like he'd be really strong as sets expand and more artifacts are added. I imagine running him in a deck with the Banners, GI and its Junkyards adding Unstoppable/Flying, mass buffing, and maybe a second purity or third faction for more artifacts could make the Collector a key card in many decks that are artifact heavy. Heck, it might even be worth running him in command if you build your deck around him.
I'm pretty sure Brimstone is Unique, even though Infinite Network doesn't list that, so either I'm wrong or IN is wrong. I'm not sure which.