Being in Hawaii, I can only get to a Disney park once every couple of years. Love them all, but I am starting to lean heavily towards Tokyo Disneyland and Disneysea. I visited Disneyland in September of last year, and while fun, the level of service and quality of souvenirs makes the Japan parks a lot more enjoyable.
Blame that on the "Disney Parks" mentality where both Disneyland and Walt Disney World share theme park exclusives rather than making them unique to each resort.
When I go to Walt Disney World resort, I don't want to buy something that's "Disneyland" and vice versa. Nor do I want something that says "Disney Parks". I want it to be "Walt Disney World", "Epcot", "Disneyland" etc.
I was ready to answer your first paragraph before even seeing the second. While in a perfect world WDW and DLR would have a lot of different merch, I would at LEAST like to see the same exact bobblehead that they sell on both coasts marked only with the park it was found in.
As I sit at my desk, I am always staring at my solar Mickey bobblehead (hard hitting review here), and the Disneyland - Walt Disney World lettering on the back always bugs me.