Looks like a reasonable deck. I'd personally try to fit in another Mind Control; it arguably is one of the strongest cards in the game at the moment. To put it in context, if you can steal even something like a Chillwind Yeti, you're still ahead (since you've destroyed 4 enemy mana, gained a 4-mana creature yourself, and it was a 2-card swing in the process), and obviously you're swinging for better.
I would drop the Twilight Drake for something more solid. Perhaps a Sen'jin, another Chillwind, Violet Teacher, or even Auchenai Soulpriest (makes your hero power incredibly dangerous, and you can shut it off when ready); just something generically along those lines. To put it in context, you have to have at least 6 cards in your hand at the time you play the Drake for it to be any better than a Chillwind Yeti. And unlike a Yeti, it's not worthless in the late game, and isn't crushed by silence.
I've never been much a fan of Divine Spirit. I know it can win games sometimes, but you lose a card by playing it, so the minion you create has to kill two enemy minions to break even (at least from a card advantage point of view), and in the process you're increasing risk exposure to removal and silence. So I find the risk/reward on this card to be too weak.
I'm not a fan of Lightwell either. If it works for you, fine, but because it's a 0/5, is usually dies without killing any enemy minions in the process. And if it gets silenced it's worthless. Once again, I've seen some games swung by this card, but I've only found it to be effective if you're already winning the game; that is, it's good at holding board control if you already have solid board control. My opinion is that it's more important to have cards that are strong when you're losing rather than when you're winning, and this card is the opposite.
Mind Vision is bad, it doesn't gain you any card advantage, and you're more likely to get something bad for you than something good (their cards are built to synnergize around their deck, not yours). Thoughtsteal is ok since it gives you card advantage at least.
I'm personally not a fan of Earthen Ring Farseer in Priest decks; you already have plenty of healing from your hero power. Now, granted, Farseer is a good card overall, but my opinion is that you should specialize into abilities that you don't inherently have access to as the class. Take that as you will, as I do think Farseer is generically a good card.
River Croc is a wasted spot. I understand wanting a 2/3, but at least make it an Amani Berserker or Sunfury Protector (the ability to give a late-game minion taunt shouldn't be underestimated).
You may want to work some silence into the deck. I'm torn between Mass Dispel and Spellbreaker. Mass Dispel is more of a tempo loss since you don't get a minion in the process, and you can't use it to silence your own minions (particularly when frozen by mages). However, Mass Dispel is great for removing buffs when the enemy minion tries to power up multiple units, and it break a dangerous minion out of stealth when needed.