the evil empire of the mouse, my secret weakness
I think that "Tarzan" was the last really good Disney movie for almost a decade (with the possible exception of Stitch), and the downfall attributes to absolutely uninteresting stories (Brother Bear and the movies I didn't even bother to see), too much straying away from the formula (Atlantis - not that bad, but absolutely not a Disney) and aesthetic experiments (Hercules comes to mind, but a lot of stuff afterwards which I didn't even see but the trailers already lacked the look and feel of a Disney film).
I seriously doubt that Disney could have been the first to get into the Shrek-territory of irony and iconoclasm (and I wouldn't particularly like a Disneyfied defused Shrek either).
Only recently, IMHO, Disney gets back on track (IIRC, since Pixar's John Lasseter has taken responsibility). I liked the last three ones (Bolt, Frog, Tangled) quite well though it is interesting how they still struggle to define a new style between the classical Disney look and the possibilities of CGI.
---
But back to the challenge. My solution is: manage to let Pixar blossom while getting it more closely associated with Disney- in effect, let Pixar remain a name known to fans while most people regard their films as Disney. Pixar's canon is full of modern classics which are clearly more Disneyish than the films of other competitors in the animation sector.
Let a handful of movies from between 1999-2007 NOT happen: Home on the Range first of all. Disney animation should co-exist with Pixar but serve a different audience and different aesthetics. Again I refer to the most recent three pictures: animals and princesses, bearable music and rather good visuals. A decent "Tinkerbell" instead of the not that brilliant direct-to-DVD one could have started this trend a bit earlier.