It's funny how a few days of polishing this game can do. The game now has 15 levels (after every 5 levels the environment should change). Woodcutter has been renamed Resource since the later levels don't have trees. At the moment this seems like the right length for a game, but I might include more levels that make the game harder (you will still be able to finish the game at level 15, but for a more risk you can go further). But that will be a future update.