Very good design. However with Mox Opal, you really don't need 22 land. Mox Opals count as free lands, so you can run less land without REALLY running less land. Also given how cheap the mana curve of the deck is, Etherium Sculptor is not at all needed, I say go with more Master of Etherium. Also you most certainly want to run Seat of the Synod and Ancient Den, and since you have nothing to proliferate cut Tezzeret's Gambit for more Thoughtcast or Cranial Plating. This is shaping up to be a VERY good deck.

Very well constructed deck. However, I might make a few suggestions. Take out Glint Hawk Idol for Etched Champion. Tezzeret's Gambit is good for the proliferate, but Thoughtcast is much more playable. Also, if you can somehow find room for Master of Etherium he's a very good option. Might I suggest 18 lands including artifact lands? With Mox Opals you can get away with running that few lands and it opens up slots for things like Master of Etherium, which I would suggest you take out Steel Overseer for as Overseer is actually slower at buffing your creatures and much more vulnerable. Lastly Cranial Plating is always good for these kinds of decks.