Navigator is also a terminal silver. You could ignore that, but that's kind of a big deal. Guide can't whiff. At worst, you can get stuck playing it in a borderline situation. You could ignore that too, but that's also kind of a big deal.
Also, Lost Arts + Gear is two Havens in a row, sort of but not really.
EDIT: I mean, if we can just ignore "+$2" once per card if we feel like it, then Cache is just three Coppers for the low, low price of $5... And if we can ignore "+1 card, +1 action" whenever we feel like it, then Laboratory is actually just a Ruined Library.....