Sometimes I see two great looking decks that are similar but rarely is it worth showing both. I've seen a few of these artifact decks pop up, utilizing the power of Ensoul Artifact, Shrapnel Blast, and Ghostfire Blade, and Todd Anderson even played his own version at Pro Tour Khans of Tarkir. Todd did a deck tech of his version of the deck, but he didn't fare so well in the tournament. Still, I think this archetype warrants a further look.
Todd's list played Heliod's Pilgrim for consistency, while today's lists played red in order to have access to several burn spells and things like Goblin Rabblemaster. I kind of like that option since this deck is great at dealing big, early chunks of damage, but closing the game can be difficult. With things like Shrapnel Blast and Stoke the Flames, even Siege Rhino isn't going to stop you.
The second decklist actually does what Todd did as well, which is splash for Heliod's Pilgrim. While it's not quite Stoneforge Mystic, it still provides a body for Springleaf Drum while finding your Ensoul Artifact, and you can't really ask for much more than that.
I know a lot of people have been working on this archetype, so hopefully we'll come to a consensus best list soon!