While I totally disagree that Robocoaster should be used for Space Mountain, don't dismiss the technology as vomit-inducing at one glance. The ride system can be adjusted to be as violent or as gentle as the designers want. The technology could be used for a new ride at WDW, and be designed from the get-go as a thrilling, but family-safe attraction. I'm sure the imagineers would use it as such. A lot of people talk about Robocoaster, however Pandora's Box seems more likely to be used for the next WDW attraction due to being a Vekoma product.
I agree that SM needs an update as far as the pre and post-ride displays. I have a nostalgic attachment to the queue as-is, but man it is really old. I still like the current music in the line, and I hope that doesn't change. At least keep one thing from the past. The track layout is fine as it is, but if they can somehow smooth it out that would be ideal. Making the trains 2-wide might pose a problem as the ride is packed into such a tight tangle of steel, but that would be great too. There's no way for us to tell what they can or can't do at this point.