In 20 years? Who's to say. I am 100% confident that Disney won't be building a third gate in Anaheim in the next decade.
The fourth cruise ship is being penciled in in long-term strategic planning for DCL. No third park is.
And I really don't understand you're negativity about the third ship. It's a done deal. DCL is going to expand. This business is a cash cow and Disney has far more demand than supply (unlike resort rooms in Orlando). It's a no-brainer.