Building on MagicFubu's comment, perhaps add a welcome screen where you can pick the speed that the snake moves at and yes adding obstacles would be a good dea but it would have to be randomly generated otherwise this might make the game a little predictble and boring. Also adding sound effects would be great, oe for the title screen selections, one for the collection of the blocks and another when you die.
Also, the look of the game is a little bit dull. Maybe you should add some fancy text words
 "Classical Snake"){kind=icon}
 "Maze Stopper 3"){kind=icon}