I don't think it would be worth it. How many parks that have a water park and a separate rapids have the park and water park in one gate? For HP there might be move value in doing something like moving one of the rights in the back, expand the Boardwalk into that space. Not that I think that would ever happen.
In all reality, they don't need one with how big the Boardwalk is, and having Coal Cracker they are still set with a non-soaking water ride.
If they expand the Boardwalk again, most likely you would see Tidal Force come out, some of the buildings north of it taken out. After that would most likely be Wild Mouse Moving.
I would really love to see them re-invest in the Midway, put a bunch of games back there, and retheme the area to a turn of the century pier park. Paint Wildcat white, take out the overflow switchbacks (haven't been used in a while) and put in some games there.
Heck on that line of thinking, I wouldn't mind seeing Wildcat shut down for an entire year to get repainted, let GCI retrack the entire ride at one time. Leave Laff Track as is, leave racer as is, with maybe a new lighting package.