Null Rod is both better and worse than it was this past weekend. It's better against Shops because it taps to Tangle Wire, but it's worse because a resurgence of Shops makes being an artifact worse in other matchups. When I really want Stony Silence to resolve, say against Tezzeret, I rarely lead with it anyway. Leading with a Thorn/Thalia either baits their Force, or forces them to play out their moxen, which gives me more information about whether they are holding a Force, or is better than a Stony would be anyway, because they have no moxen.
Hierarch solves a lot of problems with the mana base. Against Blood Moon you just Metamorph their Trinket Mage and get your Sol Ring or Mana Crypt for a colorless source. You also have Nature's Claim/Disenchants. I could see a single basic for Path/GQ protection, but that's about it.
34 Mana sources is misleading because 8-9 of our lands are also spells (Canopies/Wastelands/Strip Mines) and the 4 Hierarchs both let us use those lands as spells instead of mana and tend to deal 2-3 damage over the course of a game with exalted triggers, which is often worth a turn. 4 Hierarchs also increase the odds of T2 Thought-Knot, which puts us up a card a turn earlier than we would be. That said, I've played 1-3 Tireless Trackers in the Restoration Angel slot as a draw engine and really liked it. It clashes with Stony Silence, but usually you are winning anyway if you have Silence out, or else you are drawing into it with Tracker.
4 Thalia is correct. She is the reason we are playing white in the first place. I would much rather have two than zero. Your opponent desperately wants to kill her. You want your thorn effects on turn one. Wingmare seems good because it lets you stack Thorns, but this is mostly necessary because the mono white deck can't support Null Rod/Stony Silence. Furthermore, Because of Hierarch, we are going to 4 mana on turn 2 as much as possible, meaning the value of three drops is somewhat diminished.
Containment Priest moves to the board because Priest is awful in the Displacer mirror. I could see one or two maindeck, but as much as I love the card, I think going too heavy on maindeck Priest is a mistake.