I have to say, my favorite part of this concept is the flexibility.
In 2 or 3 years when the novelty wears off, you simply change the story around and say that the park was shut down because of a rollercoaster accident involving the death of 13 children. Now the streets of festa Italy are haunted by creepy children (like the trick or treaters at HHN). Now the funhouse is overrun by demonic kids. Exact same props, exact same idea, but completely different experience.
Once that story is played out after 2 or 3 years you change the story to the rides turning evil and killing the guests. Now you remodel the house to make it look like a family dark ride, (think its a smallworld) but evil anomotronics keep trying to kill you. It would be super creepy to feel like you are walking along the track of a ride that is trying to kill you. Again, the house is redesigned, but the rest of the props and the idea stay the same.
Then another few years pass, BGW decides to bring back the evil garden idea. Now the kiddy ride is littered with plants trying to rip there way through. Again nearly the exact same props, but a completely different experience.
Although this concepts might be expensive at first, BGW has to look at it as an investment. It would be really cool to see the way the park changes up Scotty's every few years.
Scotty's fun park shouldn't just be a house added to the list of attractions. It should be a hamlet that is permanently added to the Howl of Scream map. The GP will love it and it will save the park money in the long run.