I'm stung by Pharika following at the heels of the other JOU gods. For starters, while there is a lot in G/B right now that makes use of the graveyard, they all run counter to what Pharika does. Want to make a huge Nighthowler or Nemesis of Mortals? Major nonbo with Pharika, given she's exiling creatures from your graveyard. I could see them going in the same deck, but it'd be very awkward.
Beyond that, all the other gods have had very flashy abilities. Keranos draws cards and bolts things. Iroas makes your guys not take damage while attacking. Athreos is Athreoa. And Kruphix? I'll admit he's not the strongest (talking standard here), but at least he's got two super-flashy abilities. Pharika's ability is pretty useful, sure... but it's not exciting. At best, it's just a value play.
Flavourfully, it's kinda cool, but I don't think it plays up her dual nature. Pharika should be about the duality of life and death. To borrow from the flavour text of Pharika's Mender, "The direst venom becomes a panacea under Pharika's guidance." I mean, snakes are cool and venemous... but I don't feel an efforts been made to connect this to Pharika's dossier.
At the very least, it could make for some cool interactions with constellation.
I'm trying very hard to accept this, that I didn't get what I was hoping for. I started playing magic with M14 (not counting the one MMA draft), so I guess I'd better get used to disappointment. To be clear, I mean with specific cards, not with whole sets. Not every card's gonna be perfect (see: Mindreaver), so better to move on and enjoy the cards that are awesome.