I would agree with Kathy that the stretching room would be an uncomfortable (and possibly dangerous) place for a service dog.
For Soarin', I also don't understand why they don't have an option for people who can't transfer. If they are worried about liability from someone wandering around during the show and being out of place when the ride vehicles come back to the floor, they could have a designated wheelchair viewing space with a seatbelt or a gate that closes securely and opens automatically just like the seat belts on the ride do once the ride is over.
It also seems to me that they could have easily added a fold up armrest in some places like airplane seats have. The armrest could also 'latch' when the ride starts and 'unlatch' when it is over.
I do know from articles I have read/talking to some CMs that Disney does use panels of people with disabilities to assess designs for accessability. A lot depends on who is on the panel though; do they have similar disabilities or is there a variety and do they have the ability to see the design for someone who has different abilities than they do.
Looking just through my own eyes, I would say that Soarin' is very accessible, but I have a rather small person who can do a stand and pivot if she's having a good day and is small and light enough for us to easily lift (well, sort of easily lift) if she is having a bad day. But, I can also see how lack of ability to have a place for a sliding board or fold up armrest might hinder some people.
And, what is the best for some people (transfer to the end seat with a fold up armrest) would not work for others - we need DD to be on an inside seat with one of us on either side in case she gets too excited and goes into extension mode.
So, on some atttractions, like Soarin' , if they have one 'disability seat' that won't meet the needs of everyone.
One of the other things I have said before that would be helpful would be a 'virtual library' of ride access, with things like pictures of ride cars, information about things like moving walkways, height of the seat, do you get on and off on the same side, which side do you get on and off from (since some people can transfer better from one side than the other), etc.
That would allow guests with disabilities to look at what is available on particular rides and see with their own eyes whether they think they can get on (and sometimes even more important), get off. In the past, I have thought of that being in Guest Relations and on line so people could check things out ahead of time and print out what they needed. But, technology has advanced since then and it would be easy for them to lend out somthing (like a PDA or video ipod) with the information loaded on so the guest can refer to it during the day. They could also have ride videos so people could view them if they want to judge whether there is anything on that attraction that would be too much for them.
Even updating/upgrading their Guidebooks for Guests with Disabilities would be helpful as the information right now is so basic and so general that no one can figure out from that whether or not they can get on. It basically just tells you 'transfer required,' but a transfer to Pirates is a lot different than a transfer to Soarin' or to EE.