I would actually like an outdoor coaster that is heavily themed and landscaped (essentially the HP coaster we are getting haha)....But themed to HPI would love an indoors roller coaster with a lot of theme, but it's not something I think will happen.
I really would love an immersive dark ride, or interactive show of some sort. Something lighter would be nice since River Adventure is a bit dark and scary for the children, but at the same time I'd also love something really thrilling as well.
Essentially you'll have an HP family coaster that's a bit more intense and a JP Coaster that is a bit more traditional and fun