So... I found an exploit to get exp: countdown for the Simulation Room keeps going down even when looking at menus where the time of day doesn't move, like the Achievement's screen. That way, you can use the Simulation like 10 times a day.
"Alright men, this will be your most difficult battle ever. The enemy will have very advanced weaponry, such as missiles, mini-guns, and the worst of all: A balloon that drops Rubber Ducks!. Be on your toes for those things".
A "sell all" button in the pig's shop would be nice to have. Also, like everyone says, the green levels are horrible. what you can do about that is have some level up powers or rings special for that, like a ring/power-up that brings you things faster in those levels.