How good were Sower of Temptations for you?
They seem pretty essential. Anything with creatures can attack to bust up the combo, and Sower is like generating 3 blockers with a single card (it blocks, it takes an attacker, the stolen attacker now blocks). Against Fish, TMWA, or the R/G/W Beatz deck that made top 8, you would really need to bring those in, especially when you're eschewing other kill-cons such as Tinker Colossus.
Dan, was this ever a problem? I see that you did not drop a match to aggro, but did you have any issues with Tezzeret getting attacked? Or was Ophidian consistently enough to handle it with the backup out of the board?