Makes sense, but I'm sure Disney/Marvel have outright ownership to many untapped characters.
Yes, but that is not why you spend the money to aquire things. You spend money to aquire what is already popular and profit off of it.
They did not purchase Star Wars to need to rush to make a Tuskan Raider series.
They milked it, now they would have to put even more effort into storytelling and that market is so saturated. Maybe in five or eight years.
Theme park wise(smaller potatoes than films of course) Universal got the best deal out of it. They bought Marvel when no one else really wanted them and the sat morning cartoons became well produced and rememebred. The attractions themselves were/are amazing so they hold their own and then the movies have reawakened the longevity with a modern animated series of films and television. They have even updated and invested.
Some of it luck and the way the world just happens to work sometimes but:
This is why Marvel Superhero Island has lasted for 24 years and The Avengers Campus will have to be majorly reworked within ten.