Continually add new experiences? Since when?
Just in the last year, off the top of my head (some may be more than a year or coming soon because these are off the top of my head). Also trying to pick things that are free:
Storymaker touches to several attractions, including Haunted Mansion.
New Peter Pan queue to make it interesting.
New store for Haunted Mansion, which even if you don't buy from is more interesting to browse than a candle store.
New Star Wars fireworks being called the best ever played at WDW by some.
Longer Flower & Garden that some are calling better than Food & Wine (with a handful of free experiences).
Revamped FP+ to maximize Fastpass ability.
An entirely new section of Africa, with a new dedicated theater for Lion King.
Frozen shows at HS.
A slight re-work of the ending of the Great Movie Ride.
Right around the corner:
Soarin' (More capacity = more rides = more value)
New track for Toy Story Mania (adding more capacity = more rides)
Discovery Island Carnivale
Harambe Acrobats
Soccer Meerkats
Karibu Sisters
Muziki
Viva Gaia
Tree of Light night show
Rivers of Life (maybe not right around the corner, lol! Might be up and running when I visit again in 2018).
Only three or four of these attractions replaced something big. The rest are entirely new, or replaced something smaller or outdated. Again, I avoided things that cost more money on top of admission, but if we were to include those too you can add Skipper's Canteen, almost all of Disney Spring (something I never cared about before but now have a few stores I want to visit that aren't anywhere else), and more.