-1 Crucible
-3 sphere of Resistence
-1 thirst for knowledge
+1 Triskelion
+1 Mindslaver
+1 Windfall
+2 Meditate
I could see it argued that 2 sphere of resistance to back up 4 trinisphere is good, but I can't argue the sheer goodness that is an EOT meditate when you've got counters on the stacks and tanglewires
4 extra cards for 3 mana is worth a wasted turn most games. At least it doesn't need to be explained why timewalk is bad in stax.

Recently i've been siding chalice in to replace spheres/trinisphere, and have seriously considered maindecking them, but perhaps that's just because of my meta.