Toontown is an awesome idea. It's just been neglected. When it first opened, it built on the popularity of Who Framed Roger Rabbit, and was billed as "you chance to enter an animated world." The first time I entered Toontown (when it opened in 1993), it really did feel like just that.
But now, the paint is peeling and faded.
I love the way the road dips down under the train tracks, obscuring your view into Toontown, but that "population" sign needs some help.
The area is always too hot. Why isn't there more shade back there? Chip 'n Dale's Treehouse? Not really a thing anymore. As MWH1980 mentions above, there's no sense of life and movement.
I think a retooling is in order. I say model it after the new Mickey and Friends design (from the Paul Rudish animated shorts) and give it a new/vintage feel. Add vibrant colors and textures, and either make Donald's Boat and Goofy's Bouncehouse more interactive and playgroundy or replace them altogether.
I always thought Donald's area should be about him being jealous of all the attention Mickey gets in the park. "No mice allowed" signs and Donald-centric merchandise there would be cool.