Wishes is the only fireworks show that can be (for the most part) seen from outside the presenting park.
Good viewing can be found at the beach of the Polynesian Resort (walk along the sidewalk there until you see a view of the castle unobstructed by trees.)
The Ohana restaurant at the Poly offers good views (and they pipe in the audio of the show). Same goes for the California Grill Restaurant (and outdoor terrace) at the Contemporary Resort.
At Grand Floridian, "Narcoossee's" is the restaurant with the MK and Wishes views (and sound).
The MK parking lot (TTC) offers views, as well as do other outdoor spots for several miles in any direction of MK. But without the sound, you miss a lot of the "show".
Best analogy:
Sitting across the highway from a Drive-In Theater and "watching the movie" with binoculars. You can do it, but it LACKS something.
While "Wishes" CAN be seen and enjoyed (for the most part) from many places outside MK, IllumiNations is a different story altogether.
MOST of effects of IllumiNations take place ON (or just a few feet above) the surface of the water of the WS lagoon.
Except for the very first "Comet" firework effect, and several other major "sky-blasts", IllumiNations can't really be enjoyed from outside Epcot's World Showcase. A good 1/3rd of the show does not involve fireworks but a large "video-globe" towed across the water and tiny lights imbedded into the buildings of WS.
One favorite outside spot to view the few "sky-blasts" is on the bridge coming toward Epcot's International Gateway from the Boardwalk Resort. You can't hear any of the music track, which is a very important part of the show.
You can't see very much either, and there will be very long periods of time where you see nothing at all.
There are a few villas at the Boardwalk that have (obstructed) views, and there are limited views from a beach at CBR, but as stated above... you will not see very much, and what you DO see can't legitimately be called "IllumiNations."
