There's also the beach at Ft. Wilderness. You can also sometimes see them from one of the shuttle boats. WDW sadly stops the monorails during the fireworks, so don't expect any view.
In addition to Cali Grill, there's also 'Ohana, but the view is partially obstructed: some tables have no view, a very few have an okay view, most have a partly obstructed view.
The monorail hotels offer rooms with a MK fireworks view.
There are some significant limits if you see the fireworks outside the parks.
First, you miss the castle light show. When it was Wishes, it wasn't so bad, but the projections are a BIG part of the new show. Also the fireworks are at odd angles relative to the castle from most locations outside the parks.
Second, if you ARE in one of the locations that has speakers, the volume is VERY LOW! If the people near you are talking, you can't hear.
I think it is VERY rude of folks to do that, but there isn't much you can do about it. I dare say, in my experience, a significant percent of the adults who are watching HEA from outside the parks, are folks partaking of adult beverages. They don't realize they are obnoxiously loud, and maybe not receptive to requests from strangers.
So, it doesn't end up always being all that great of an experience.