It seems like the deck is slowly moving away from being a discard deck and going towards being a sacrifice-trick deck. If choose to go down that road, I suggest you look add the Ravnica set and check out some Golgari cards. Putrefy is great removal and Golgari Germination would be very nasty with Skullclamp. (and yes, tokens do trigger graveyard triggers, such as the Clamp)
But, I'll try to keep it monoblack.
Have you considered using Words of Waste? With that enchantment out, you could pay (3) and sacrifice a creature to let each other player discard two cards. Delerium Skeins could also be brutal and lets you discard cards as well, which gives you a way to dump Caretaker targets in your graveyard.
I agree that the deck might need some kind of token generator; right now you can hardly use the Hell's Caretaker. Something like Sengir Autocrat or Snake Basket perhaps?
I see you are considering dropping the two Dark Rituals: I couldn't agree more. First turn Hypnotic Spectre is nice, but Dark Ritual, to me at least, is a card that can only be played when you play four.
Consequently, I would also drop a Drain Life (and perhaps both). Seeing that you are a discard deck, your deck takes control of the board and then can use just about anything to kill your opponent. I feel Drain Life doesn't help this game plan (if you establish control, it won't really matter how much life you are on and you still got the Bottle Gnomes... and playing it before the board is yours simply prolonges the state of the game your deck doesn't like)
(PS It's kinda weird responding to a revised opening post.. and also makes reading the thread again really weird.. but of course its your thread and you can do with it what you want
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