Bear in mind that if you are going for Millstone / Brain Freeze win you will have trouble winning against decks that uses
Gaea's Blessing.
It's not as common as it was before, but I suggest include
Jester's Cap. The cap is just pure evil against combo and can remove Blessings as well.
I can't see how you are going to make use of Standstill when you got no manlands. You need a guiltfeeder in the board before the Standstill and waiting 6 turns before putting a standstill in the board is to long in Type1.
I think the Solution at card advantage is not Standstill but Brainstorm. I think that Thran Quarry isn't needed and I suggest putting inn Polluted Delta. They also can fetch all of the dual lands.
Manabase:
-2 Thran Quarry +2 Polluted Delta
Draw:
-4 Standstill +4 Brainstorm