Mickey Bars and similar style 'Good Humor/Nestle's' (?) products are ubiquitous. Yes, the Ears do taste better.
Hand-dipped ice cream is all made by Edy's.
Auntie Gravity's sells soft-serve.
There's waffles a la mode at Sleepy Hollow.
Shakes at 50's Prime Time (PB&J) get mentioned often.
L'Artisan des Glaces in France is 'gelato' (which is an Italian word) and is creamier than American-style ice cream. This would be my 'in Park favorite'.
Ghiradeli's in Downtown Disney is made by Edy's, but also has a few specially formulated chocolate flavors that are decadent.
Downtown Disney has a Hagen Daz.
There is also a
superior Gelato parlor, Vivoli Gelateria, that opened this past year in Downtown Disney that makes all their own products.
At the Resort - Beaches'n'Cream is a standout (Edy's), and Fountain inside Dolphin get their product from a local artisanal maker. Honorable mention to the bottomless Shakes at Whispering Canyon.
I'm sure I've missed a few others.