Gosh, everyone on this board has such a different opinion! I will comment on things you don't have in Cali.
Illuminations, the fireworks show at EPCOT is a powerful work of art. Quite the experience.
World Showcase: the architecture is stunning to see, and the performances are all worthwhile. The movies and rides, not so much. Do a ride (Mexico, Norway) only if it is easy, do not wait on a long line. Skip the movies entirely.
Make sure you look closely at the Entertainment Guide for WS. Acrobats from China, clown in Italy, Server Amusant in France, UK Players, Candy Making and Drummers in Japan. Mariachi plays in Mexico while you shop, eat. These are all highlights. Mo Rockin in Morrocco, British Invasion, and Off Kilter in Canada are all bands playing in a theatre-style setting. - YMMV.
Restaurants in WS are not only places to eat but are truly something to see/experience.
Future World:
Mission Space is a big deal. Orange line for the full effect of G Forces on your body. Will dump you into a game room with a couple of very fun games.
Test Track: A highlight for many, get an FP for this.
Ellen's Energy Adventure: This takes 45 minutes and is not a highlight for many. A very unusual hybrid ride/theatre experience. You have my permission to miss this if you are pressed for time.
Spaceship Earth: A highlight for many. Twenty minutes, plus will dump you into a game room with some pretty cool games. Competition for games will be intense.
Innoventions: Much larger, many different games and experiences than in LA, still, you get the idea.
Figment ride: A highlight for nobody.
Ride in the Land Pavillion: Not a highlight either, but many enjoy this.
Movie in the Land Pavillion: Most people skip this.
Finding Nemo Ride: Most people will find this disappointing after the Subs in LA. Most people mistakenly believe they HAVE TO ride this to enter the Seas Pavillion. You can avoid a long line here by entering the pavillion to the left. Still, worth doing if you get here first thing in the morning.
Seas Pavillion: aquarium attraction. YMMV.
Take some time to look at the fountains at EPCOT. A highlight.
There is also a pavillion in which you can taste sodas from around the world. Everyone seems to enjoy this.
Also, try to catch the entertainment in FW. Check the daily guide.
AK Rides.
Expedition Everest: A highlight for many. You will probably want to try this twice.
Kali River Rapids is a sad version of Grizzly River Run. This is a highlight for many, but DL folks will surely scratch their heads.
Kilimanjaro Safaris: A highlight for many.
Dinosaur: A highlight. You may want to do this twice.
Shows:
Festival of the Lion King, a highlight for many.
Finding Nemo:a highlight as well. TIP: Sit as far back as possible.
Flights of Wonder: Unusual bird stunt show with lame comedy. Painful, but the birds are great.
Parade; Clever,fun.
Check the entertainment guide for performances at the Dawa Bar in Africa. The Congolese Limbo Dancers are amazing.
Animal places:
Pagani Forest Trail: Best very early in the morning or maybe the last thing, when nobody is here. Otherwise gets very crowded.
Maharaja JungleTrek: Some beautiful sets.
Oasis: beautiful, fun, unusual.
Rafiki Planet Watch: Most people skip this their first visit. Is time consuming.
DHS Rides
Rock n Roller Coaster: A highlight. You may want to do this twice.
Great Movie Ride: twenty minutes, a likeable experience.
DHS Shows
Beauty and the Beast: short and sweet community theatre. Don't waste your time if you are expecting Alladin. A good show for everyone else, but LA folks will be deeply disappointed.
Voyage of the Little Mermaid: For the very young.
Playhouse Disney: For the very young.
Lights Motor Action: A highlight.
Indiana Jones Stunt Show: A highlight.
Backlot Tour: An unusual hybrid attraction. A highlight.
Sounds Dangerous: Likeable. Many people miss this or don't care.
Movie: Disney, One Man's Dream: A highlight.
Narnia: Trailer for the movie. Almost everyone skips this.
American Idol: A highlight. You may want to go more than once.
MK
Carousel of Progress: Nostalgiac fun, a Disney Classic
Country Bear Jamboree: Ditto.
Stitch: Almost everyone skips this the first visit.
Monsters Inc Laugh Floor: Like Turtle Talk but not as good as Turtle Talk. Fun.
Mickey's PHILHARMAGIC: Almost everyone agrees (finally) that this is Disney's best 3D movie.
Spectromagic: almost everyone agrees that this is the best parade at WDW. A highlight.
Others:
Hoop de Doo, most people find this worthwhile, but it is not considered a highlight.
Disney Quest: Same as above.
Buskers on the boardwalk. Free entertainment. Fun and high quality.