I know you can see Wishes from the Contemporary hotel... I would assume you can see it outside the park fairly easily. You can also see it from the Poly, and stand on the beach there. I THINK you have to be a guest to stand down there, not sure...
As far as Illuminations, the show itself is really on the water, so you might be able to view the higher fireworks from the Boardwalk area, but you miss the gist of the show. Make sense? Its not just a traditional fireworks show. =)