Piracy Charm :
It's not a great 1cc card but may be useful in your
Megrim/Caress strategy and you can use it to remove a
Dark Confidant or Thalia as well in a pinch.
Playing it early and hitting a land may not be all that effective.
Playing it late, with a couple of your enchantments out could be nice.
If you decide to use the card, I'd suggest no more than 2 since you really don't want to play them early or get them in your opening hand.
Liliana of the Veil :
Her -2 ability can be pretty devastating if your opponent want to use 1 beatstick to grind you down and if she gets to her ultimate that usually means game over.
Regarding your deck :
The way I interpret it,
It's built around
Megrim/Caress, so you want these out asap BEFORE you hit your opponent with discard spells.
That brings me to
4
Dark Ritual4
Liliana's Caress4
MegrimAn opposing empty hand is bad for your strategy, so you need cards that put permanents back in his hand and make him discard
4
Recoil4
Blizzard Specter ( Ritual it out T2 if possible )
Get more use out of your Recoils and other instants/sorceries
2
Mystic Sanctuary2
Snapcaster MagePut cards in your and your opponent's hand as discard fuel
1-2
Jace BelerenSuccess.