Mask of Memory could be a decent draw engine, as you're not running Null Rod. Grim Lavamancers are a good idea, not only giving you removal, but giving you repeated removal when you need it, and a good target for Mask if you so choose to run it. Birds of Paradise also seem like they should definitely be in here. First turn 3Sphere is just plain brutal.They also seem like they would make a decent Mask target late game when the mana accel isn't needed. What about some kind of man-land?  know they're slow, and this is a tempo deck, but they'd be decent if the other guy lays down a 3Sphere and don't hurt against Oath, as well as being uncounterable,albeit slow, versus the aforementioned Drain-based Control. I could be wrong but it makes some sense.