I wrote something like this once before somewhere else. When Disney does a new ride I expect one of two things to be creative. Either the ride system, or the execution of the ride entertainment (story). In my opinion that is what they pay the Imagineers for, to make one of those two things different and special. The ride system for Splash Mountain isn't particularly creative. It's a flume ride as you said. For Splash, it is the execution of the ride entertainment. The story is beautifully told with the scenes and animatronics. The colors are wonderful. The music is spot on. The ride compliments the story, with the big hill coming at the climax of the story and the drop perfectly matching the danger of that point in the story. Truly, it is beautifully executed.
When you contrast it to Little Mermaid, where both the ride system, the ubiquitous omnimover, and the retelling of the story has no elegance or twist, you can see the difference between what I expect from Disney, and what they have sometimes provided. Another good example is Peter Pan. There it is the ride system. Yes it's an Omnimover, but the suspension from the ceiling immerses you in the flying experience, so strongly a part of the wistfulness of the underlying story, that it is a fabulous adjustment. I like 7DMT. I appreciate that they didn't simply re-tell the story, instead they borrowed 3 components of the story and executed them well. Do I wish it was longer? Less of a kiddie coaster? Yes I do. But I appreciate the concept of the swinging barrels, even if I wish they made the effect more elaborate, the beautifully rendered cavern, and the well executed House in the Forest. It doesn't simply retell the story or load you onto a moving car with music, it instead augments a ride with moments of scenic brilliance.
As for another one that is done all wrong in my opinion? Look no further than the money grabbing FEA, which was shoe horned over a much better ride. If you are going to overlay an IP into a genuinely good existing ride, don't puke it all out into a storyboard like FEA does. Overlay it with subtlety and creativity, like they did with Pirates.
In the end, I think Splash is the best from the Imagineers of any ride that wasn't part of a Park opening. I think there are some original Park rides, like Spaceship Earth, Pirates, Haunted Mansion, and AK Safari that are of the same class or better. But of the rides that have been added to the Parks since they opened, I think it is hard to top Splash Mountain for a ride that would have been approved by Walt himself.
