Cthulhu board: This one is actually kinda nuts. Sacrifice is the star of the show here, turning all those damn Ruins into engine fuel to the point where I wonder if you can actually make a nontraditional engine fire out of these pieces using Sacrifice as your only source of plus Action. Ultimately the lack of +Buy kills it, but with Haunted Woods and Cultist chains for draw, Conspirator for payload, it almost had something to it. Sad.
You'll want to buy Curse opportunistically, probably one time after you dud due to too many Ruins. There's a cool thing you could probably do with Altar or Graverobber and Ritual where you gain a Curse to get points, then use Altar to gain a $5 and trash the Curse, etc, but who knows how well that actually works you know. This probably ends up just not being a super fun board. BUY HAUNTED WOODS.
Flava Flav: It's a Vineyard board! I think the piles you want 3+ of are definitely FV, Butcher, Baker. maaaaaybe Wine Merchant (keep some out of the way on the mat!), and probably Forager. I would honestly consider skipping Spice Merchant in lieu of three Forager for the bonus even if they end up being dead weight? I dunno man. HoP can't be that bad here, either, but just as an Action gainer that you Butcher into something else late.