Agh my brain is seriously not shutting up right now haha... Just thought of a story version where you're a soul possessing the scarecrow, and when your job is done you shoot up and fly to a new farm... You could have a lot of variation on plant/critter species mix and weather variables, with staged difficulty, and possibly some upgrades between "lives", with some ultimate story about... hmm either some spirit that hears the plight of various farmers or some "minor deity" of scarecrows, or the soul of someone (farmer or landowner maybe) who needs to pay back some kind of soul debt/learn a lesson or can't move on. Ok that's me done!