I really doubt it will be a scare maze. They're iffy with operation the water slide because it requires 3 ride ops...
I would say something like a retheme for one of the dark rides would be a possiblity.
They're also getting some kind of Splash Zone attraction, which is likely to be similar to what one of the Gullivers parks have.
Its kinda odd really, they have that poll on their website, asking what you'd like to see new for next year; Haunted House, Swimming Pool or new ride. New ride is winning, yet so far, they are getting the two loosing options! BUT, whatever, its just good to see FI interested in adding new stuff again, its been a while....