Here's the thing
Stitch will get more visitors in the short term because, as DukeEarthwalker mentioned, Stitch is a recognizable name and character.
However, Stitch won't get as many repeat visitors as AE did. AE had a cult following, which is something Stitch will never have.
Another thing that AE had going for it (besides the many reasons listed above) is that it's timeless. Stitch is based on a current character that will likely fade into the dustbin. However, AE isn't based on anything current or specific to any time or place. The story and attraction are as valid now as they will be 100 years from now. Not so much with Stitch.