In my mind, the best was the updating of Mission to Mars to Alien Encounter. My expectations for AE were zero. I had no idea what they could possibly do with such an antiquated attraction and limited space. However, I was totally blown away by what Imagineering was able to do. The creativity on display was breathtaking. It took the basic concept and made it better in every conceivable away.
The worst has to be the utter decimation of Journey into Imagination. The most popular attraction at Epcot full of wonderfully colorful scenes and incredibly imaginative vignettes and characters reduced to a science lab. Horrible.
I throw it to you. What are your favorite/hated updated attractions.
Other contenders could definately be Stitch's Great Escape and Tiki Rom Under New Management
Oddly, I initially felt the same way about the Bizarro-fication of the floorless Medusa at SF Great Adventure. But that ride is now fun for me again, and has regained its spot in my Top Ten steel coasters.
Imagination was also the worst single mistake, to the point "Save Figment" was born and was successful. However it still can't hold a candle to the original ride. With some luck an update will be in it's figure and they can correct the mistake properly this time.
Mr. Toad to Winnie the Pooh. Now I like Winnie the Pooh, he's a favorite of my childhood but really. There is an entire expansion going on, they couldn't save Pooh and keep Mr. Toad? Really Disney?
And via my husband: Oh! 20k leagues into.. a concrete playground that's now gone! Great re-theme there!
Now, onto other parks.
Now, USO did re-theme Back to the Future which was a classic ride however I personally think they did Simpsons very well for what it is.
Kennywood re-themed their classic "Old Mill" ride with Garfield's Nightmare. It's bad to say it mildly but apparently has appealed to small children better then the classic "skeleton" theme did. So sadly we're got an extension on having that sadness kept around but at least they haven't torn it out like they did the Turnpike for a baby coaster. *Anger*
This is probably due to the fact it was really the first "Scary" and "Dark" attraction at WDW. Some of us jokingly call the mid-1990's as WDW's "Emo Peorid" since it also gave us Tower of Terror as well as the beginning of additions to Haunted Mansion. Plus it's also the ending year of some classic attractions.
Best: Steel Phantom to Phantom's Revenge--This was a grand slam home run that took some serious chutzpah to pull off. Steel Phantom was already a top 25 roller coaster, but Kennywood saw the popularity and increased accessibility of the hypercoaster, and made a great coaster legendary.
Honorable mentions to Wildcat at Hersheypark with its new Millennium Flier trains (Gwazi would probably be here too, but I haven't ridden since the change) and the 2011 upgrades to Intimidator 305
Worst: The 2010 "upgrades" to Intimidator 305 (trims on 1st drop)--The transition to the softer shoulder straps was a good upgrade, but there's nothing worse than turning a 305' drop into a sub 80 MPH top speed. There's nothing worse on a roller coaster than knowing that you're being slowed down one of the highest and steepest drops in the world.
Honorable mentions to the overhyped X2 (sure it's better, but not millions of dollars better) and Loch Ness Monster (trims before first loop, elimination of interlocking train spacing, and ripping Nessie out of her lair).
Best: World of Motion to Test Track--I do enjoy Mission: Space more than Test Track, but I don't really consider that an upgrade since the new attraction doesn't hold any similarity to Horizons. Test Track is exactly what Walt would have wanted in EPCOT with a perfect mix of education and excitement.
Honorable mentions go to Alien Encounter (R.I.P.) and Finding Nemo: Submarine Voyage.
Worst: Stitch's Great Escape--There's nothing that can top screwing with one of the best upgrades ever done to an attraction by neutering it. Sure A.E. was scary, and probably not appropriate for everyone entering the Magic Kingdom's gates, but the Stitch overlay is simply atrocious.
Honorable mentions go to Tiki Room: Under New Management and R.L. Stine's Haunted Lighthouse (quite possibly the WORST 4-D movie of ALL time).
That attraction is GODAWEFUL. Sitting in the pitch dark for 5 minutes listen to children scream in horror while you have stinky air blown in your face COULD NOT POSSIBLY have sounded like a good idea when that abomination was first brainstormed...
Turning Back to the Future into the Simpsons was another mistake. BttF was AMAZING and totally new (in my knowledge) to its time. The only thing they've changed is the film and the plastic theming in the quueing area. For something I was SO excited to ride, it was a big disappointment.
I'm struggling to think of anything anyone's changed for the better...
I also got dizzy, much like I did with BTTF. Wish that would have been covered up with the refurb too.. though that would require brain surgery.
Worst - Astro Orbiter at Disneyland. I'm not really saying that it's the worst ride in the park. It's an OK ride on its own, but it really sucks in comparison to the previous Rocket Jets that once stood on the tower in the center of Tomorrowland. The current version is only on the ground level where it's less exciting. This is one of the two main reasons why I find Disney World's Tomorrowland a million times better than the one here in California, along with the fact that the WDW Tomorrowland still has a version of the PeopleMover running.
I'll admit that I'm not crazy about the changes to Pirates of the Caribbean. The additions of Johnny Depp and Geoffrey Rush feel too forced and take me out of the ride. I would have preferred they simply made a separate ride based on the movies instead and left the original alone.
The update to the Haunted Mansion is what I consider should be the blueprint for every update of a classic attraction.
Don't get me wrong I still love Haunted Mansion but I feel as though it has lost its bit of fright that it use to have. No it was never intense but still less than before. Oh, and I also miss the room that you used to stand around the table in. What happened to it?
THM has never been a frightening experience for me. When I first went to DisneyWorld at 6-years-old, I was absolutely terrified to ride Space Mountain. However, I had zero problems with THM. Fell instantly in love with the evocative, without ever being terrifying, mood of the ride. I was actually more scared of Snow White at that age. I don't want to hear it. ;)
Having been on both the original and renovated versions of The Mansion dozens of times, the basics are essentially the same. There are less of the pop-up ghosts at the end of the ride, for what that is worth, but I find the new bride to be more sinister. The stairs are also much improved from the generic spiderwebs.
I also can't say that I'm aware of the standing table room that you are referring to. Unless you mean the Madame Leota or dining room scenes which are, IMHO, better than ever.
Without fail, they were all crying, all bound to be up that night with nightmares. Having been the third time I saw this particular outcome, I had to chuckle a little bit (I know, it's kinda mean, but seriously, that ride had big 'THIS IS A SCAREY RIDE' signs all over it, why people even thought bringing their young children on it was appropriate is beyond all reason.)
Yes, changing Alien Encounter to Stitch was horrid, and I would bet that even Disney hated to do it. But, as we all know, people sometimes don't read signs that say that certain rides might be inappropriate for children. Alien Encounter ended up being a fun ride at the absolutely wrong park.
As for best retrofit, I might be in the minority and say I like The Simpsons Ride more than Back to the Future. Mind you, I am a huge Back to the Future geek, but that ride did not do it for me. I wish it did, but it kinda fell flat. For me, it was an improvement to go to The Simpsons there.