Show fallen-into pits as [/] instead of as 9
Increase default difficulty to make for a better test
Allow banners to be removed, and ignore clicks on banners
Put 'say' text into the label again, and cut it down to what's actually interesting
Show stats on game solvability
Auto-dig A1 to start the game
Show a message when you, well, die :)
More compact default grid. Definitely need to make it configurable though.