I think the best viewing area has been covered but if for some reason you can't go to kse the views from most parks on the river near Titusville are a good.

As far as likelihood of launch SpaceX is the most frequent and reliable. The most exciting SpaceX launches are when the boosters fly back to the landing zone. Other than that try to catch a launch in the afternoon, evening, or night. Morning launches have the sun behind them so are harder to see. Right at sunset is my favorite. The most recent Oneweb launch you could see the booster all the way up to separation and then all the way down to landing with the naked eye. Never lost sight of it.

Also there is a new Marriot on the river with a rooftop bar they call the Space Bar that has viewing parties for guests if you stay there. It's a great view