Sadly the damage inflicted in the 2008 "refurb" and subsequent removal of the exit speedramp will most likely never be corrected. In addition to the rough ride and arguably dangerous track conditions here's a (partial?) list of self-inflicted wounds:
1) Annoying safety spiels playing repeatedly through the entire queue.
2) Lack of an entertaining preshow in the main queue switchbacks (with apologies to anyone who disagrees, the FedEx "SMTV" video loop was totally awesome and tied in perfectly to ethos of the 1994 Tomorrowland-- including advertisements for XS Tech!)
3) No longer being able to choose which side to ride.
4) Being forced against your will to endure the claustrophobic, unthemed, trashy, brightly lit and stuffy back hallway because the powers that be couldn't figure out a way to route everyone through a queue they just spent millions to refurbish.
5) Closing in the queue ceiling. Destroys the anticipation of seeing the ride vehicles from the queue and obliterates a large part of the Peoplemover experience as well. Pro tip: We used to ride the Peoplemover to check out how full the indoor SM queue was before deciding to get in line (good times, sigh).
6) Lame attempt to incorporate music into the ride with cheap DJ speakers instead on an actual on-board audio system.
7) Installation of speed brakes before the final drop.
8) Removal of the exit speedramp. Inexcusable.
The SM experience was SO much better back in the day. I feel sorry for those who never got the chance to see it for themselves. The lack of respect WDW has shown for what was once the undisputed hallmark attraction for the entire resort is another prime example of what decades of penny pinching, mismanagement and lack of knowledge of your own product can achieve.