Boy, it's taken me a long time to figure out what to write here, here goes!
Fly-Eagles-Fly, thanks so much for your interest. Archaeologist and Mastermind will use your suggested wording!
Boulder Trap I'm still pondering the wording on. I basically want the rule to be "you pass this around whenever you discard it, but if you forget, you can't go back and change it." Fun...
On Pyramid, the exactly 2 is to remind people that they need to trash 2 cards; trashing 1 card is not allowed. I do feel that the -VP is needed, first to counterbalance it (it's quite powerful) and to make it interesting, since you have to trash it before the end of the game or suffer the penalty. I also think that the Pyramid is probably the most risky design left in the set.
Sarcophagus differs from Band of Misfits in that it triggers the on-gain and on-trash effects of the targeted cards, and runs down the Supply piles. Originally played the card multiple times (like a Procession that targeted the supply) until someone here pointed out that it was far too strong. So I hit it with the nerf-bat a lot of times, and now it gets rather close to Band of Misfits. Seeing as I have a bit more time waiting for Renaissance to launch, I might take it back to its roots and try variants on it.