We've seen the fireworks from the Formosa Gardens area homes and it's not that exciting. The home we're staying at in Windsor Hills says it has a fireworks view from the upstairs window. Some of the homes in the north 27 area probably can too.
Don't base your home choice on this, after seeing it once you won't even care. Fireworks from that distance and without the music that goes with it when you're at Disney just isn't worth bothering with. You'll be happier with a home that has the amenities and location you want.