Actually you can see the launch VERY well on a clear day from anywhere on the Disney property (or kissimmee for that matter). The only thing you need to make sure of is that you are away from anything directly facing east. dont stand where a tree is blocking your angle pretty high up facing east. Just give yourself some room to see the eastern sky and you're good to go.
Warning: If it's really hazy, cloudy or rainy obviously, you may as well not waste your time.
Night launches are even better than the day.
The launches during the day from Disney are cool, but pretty much just look like a jet with contrails, except it's going up instead of across.