As much as I'd hate to see the waterfall go, I agree it's been rendered completely pointless now by being squished between the aquarium exit and the cave entrance. I know it'd never happen at this point, but I'd be happy to see the aquarium and the cave connected seamlessly (and having no light at the end of the tunnel from that gap reflecting off the screens during the day would probably make the whole thing pop even more, in my opinion). Inside the cave, then, I would continue the initial aesthetic of the ride leading up to the aquarium entrance by having more fossils in the cave walls around us to at least visually spruce up that section as we round the corner and the Stegosaurus comes into view.
In the stretch between the adult Stegosaurus and the Parasaurolophus, I - like most people have been saying - 100% would love those compies back in their old spot to the left, but I'd even take the old Psittacosaurs somewhere over there it it meant getting another species on the ride.
Ultimately, Predator Cove getting a rework - coupled with the Indo finally going into A mode - is going to do wonders for this ride, though I'm keeping my expectations about what's going on in the Cove in check. As much as I hope they're not just dropping a Gyrosphere in there and calling it a day, I'd rather not get my hopes up. (And for the record, I'd love to see a couple animatronic Pteranodons perched around Predator Cove at the very least, because having no dinosaurs at all for over a minute-long stretch between the Para and the first raptor on the lift hill is brutal.)
Edit: Also, sidenote -- the entryway leading into the T-Rex Kingdom before the lift hill would also benefit, in my opinion, with some light fog. Especially at night, some ominous ambiance like that would be really cool as we move through it and onto the lift.