I like the idea. A few suggestions: It would be good if there was some mechanism to change the values you don't pick in some way. As it stands, there's not really any reason to avoid bad squares, because you'll have to hit them eventually. There also doesn't seem to be any limit to how many turns you take or any way to fail.
Also, from a practical standpoint, you should include a web export next time. You'll get more people to play and rate the game if they don't have to download it.