Thanks! I'd love to use Erebos, but sadly my budget is extremely restricted at this point in time. I do agree he'd fit well into this deck.
I hadn't considered
Sanguimancy, and it may be worth trying out as a one of. I think the biggest issue with it is that it requires me to already have a good board presence - it can't help me pull back on an empty board. But it could be worth the experiment. I suspect I'm missing something here, but it's also worth noting
Graveborn Muse costs life, it can't help regain it, though I do find an unanswered Muse usually lets me draw rapidly into my next Grey Merchant of Asphodel.
Thanks again for the suggestions.