I think that may have a better chance, with someone overseeing the project for quality control... They're not going to want a re-do of the 1990s Mario flop on their hands after all.
But yea, I'm super disappointed that Illumination seems to be going downhill... Who knew that rushing the preproduction stage on something like a 3D animated film would result in mediocre films. Oops. Maybe they should start taking an extra 3 months in the writing phase going forward.
As for Seuss Landing, I think the biggest concern was that the Grinchmas Jim Carey-esque style character be replaced with the new Illumination one. Other than that, I don't see anything else possibly changing around there, even if the film was a success. During non-holiday times the book version of the Grinch does meet and greets, so it would only be the holiday overlay I'd be concerned about.