Is there any Doomsayer replacement? If there is, what rank do you think the deck would reach?

I currently don’t have enough gold saved up for an adventure, so I wonder if there’s a substitute for Imp Gang Boss? Will the deck still work properly without it, and what reachable rank do you think this deck can come to?

Any replacement for Lavashock?

And also, what rank do you think this deck can reach to?