I found this thread here and the forum member who created it has, in my opinion, a possible way of adding a Toontown to the Magic Kingdom. I'm going to put up the post in question:
http://forums.wdwmagic.com/showpost.php?p=4680339&postcount=7. However, unlike the rendering in the link shown here, there won't be any Storybook Land/Casey Jr. area next door. It will only be Toontown, which I actually will rename to Mickeytown, so that Toontown itself can play a bigger role in the Studios.
Also, unlike the rendering in the link, it will not be an complete duplicate of the Toontown in California. For one thing, Mickey and Minnie's houses will be combined into one, a la the Mickeyville concept. For another, there won't be a Roger Rabbit ride here. Instead, it will be another dark ride in its style, but themed to Goofy.
And if we used the tunnel like in the rendering in the link, we could bring out a sketch of the land that was thought of for the Disneyland Toontown, but not entirely used:
http://2.bp.blogspot.com/_OO7WbmARD08/SeJgu1iG1oI/AAAAAAAAQKo/wIv7zo6FRkc/s1600/ToontownElevation.jpg. If you looked at this image, the area marked "tunnel" could be one of the portals into or out of Mickeytown. Meanwhile, the area marked "grocery" could be used as an actual walk-up fruit stand. It could be just a real fruit stand, judging by the produce on display in the image here, for people who want something quick and on the go.
Just my ideas for how we can make this work. Again, what are your thoughts?