I didn't intend for the Island option to exist, though I can see why the wording makes it seem so. It should have read:
"Set aside the bottom card of your deck, then either trash, discard, or return the set-aside card to your deck, without ever turning the set-aside card face up"
At $2, doesn't it compare in power to Raze? Raze is better than Oyster when it trashes Estates, and worse when it trashes Coppers and Curses, but at least Raze won't ever accidentally trash a Province (except via online mis-clicks).