Well, its not a bad idea really. It would take a lot of work and planning. But I think that it could work well. Going back to the previous comments, I have to say that Disney's Animal Kingdom is looking for new ways to bring in crowds. Owning more land than you are going to use is necessary for such a venture. Kings Island does have this advantage. ( and if I may say so it was Walt Disney's advice to the original owners to purchase so much land )
I used to work at Paramount's Kings Island back when I was in High School. I worked at the park from 1995-97. And I remember what a sad loss it was to lose the Wild Animal Habitat. I was even taught about their high success rate in college.
Now, that all of this school work is behind me, I am a keeper an Disney's Animal Kingdom. And its true. Parks need to be original to draw in a crowd. And Animal Kingdom seems to draw in a crowd all it's own. People are so devoted to the field that a park like this covers that they will come and see it over and over again in much the same way that people will ride a roller coaster over and over again.
I would LOVE to see a zoological facility come back to Kings Island. And I think a lot of other people would too. Its a proven spot to attract a crowd and to co-exist with the Cincinnati Zoo. ( Which I also volunteered at as an educator during college) If I'm not mistaken, if you go back to the Center for Research of Endangered Wildlife C.R.E.W. at the Cincinnati Zoo, you will also find plaques honoring the accomplishments of Kings Islands Wild Animal Habitat. It's not impossible, and it would be a massive accomplishment for the field.