MK fireworks are very castle centered now. The only firework show that would work to be seen from around the park would be Fantasy in the Sky! with not castle pyro. Even then, people are want to see the fireworks in front of the castle.
DHS old shows would work if they piped the audio to outside the park and could be viewed from the parking lot in cars, but SW:GE and the new pyro set up on the Chinese theater wont let that happen.
SWO did the right thing and inform guests where to view the fireworks around the park and give several options. Their fireworks work from any angle and don't need a castle in front of them.
USO: They could use their newish WOC style show and seating area, but their old shows (that are all over the lagoon) would work better.
Island could do a small show in the lagoon, but vital viewing areas that used to be available, are not anymore.