I think some of the reason current rides are poorly executed is that they are trying too hard to be visually amazing and interactive. They end up focusing on the wrong things like show buildings, interactive queues, and skimping on presentation and story. Hear me out on this.
7DMT: Instead of focusing on a great story, they spent a lot of time making a "swaying car" which can't even really be noticed, an amazing show building, but let's face it...you can't ride a show building, and an interactive queue which again, isn't the ride. Once you ride it, you realize it's a scene too short and the ending seems like an afterthought. The building is beautiful, but it's like the entire budget was spent on that alone.
Test Track 2.0....Disney spent all this effort and money on the queue, building a car, designing it, etc etc. When you actually experience the ride, you quickly realize it has absolutely no impact on the ride itself and the execution on integrating the car you built is lacking. Once you've done it twice, you just want to skip all that and get to the ride. The queue has almost no repeatable factor.
Voyage of the Little Mermaid: Seems almost all the money was spent on the building and queue. The ride is a letdown.
My suggestion for future attractions is a relatively simple show building, simple queue, and amazing story and ride experience.
Even Peter Pan was brilliantly executed on a small budget, utilizing a unique ride system, perspective, and creative touches.
The best attractions have everything, like Tower of Terror and Splash Mountain, but the Disney of today has smaller budgets and seem to "waste" money on non-show related touches. If they are going to cut back on attraction budgets, they need to sink as much money possible into the actual ride.