These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Wasabi and Honey Lemon no longer being Japanese. Also the issue of Fred no longer being Ainu.
People are complaining about how Disney seems to once again be "reusing" the Rapunzel face for female characters.
Whether Disney adapting a Marvel property into an animated film is a revolutionary step for the Disney Animated Canon, or just an example of them forcing the Marvel Cinematic Universe into everywhere. For its part Disney has made little mention of Big Hero 6 being a Marvel property (aside from mentioning been "based on the Marvel comic series" in the trailer), and has explicitly said it's not a part of the MCU.
Strangely enough, based on interviews it looks like the opposite is what's happening-i.e. Marvel is taking a hands off approach in regards to the Disney flick (but not because, that they have a rift as the Hate Dumb would suggest) and are not even distributing the original comics (In part, due to the movie being radically different from the source material, and as Marvel Editor In Chief, Alex Alonso states that doing so would only confuse film-goers ), Yen Press is handling the tie-in manga.
The mixed heritage the film shares between White and Japanese - notably the immigration of the comic's Japan focused setting to the now fictionalized amalgamation "San Fransokyo" and the apparent Race Lift with some of the cast (notably Honey and Wasabi). While some view this as a bold change by Disney to become the first animated film to prominently feature individuals of a mixed heritages, for others it brings back some very unfavorable memories.
Cargo Ship: Many shipped Baymax with soccer balls as soon as the first trailer was released.
A few people had compared Honey to Princess Uni-Kitty. Both female characters are openly feminine with big eyes and Hidden Depths. Plus their voices sound somewhat similar and they bounce when they walk.
Internet Backdraft: The people who hated on Frozen for using similar models for the female characters have now directed their anger at Honey Lemon for the same reasons. This was somewhat mitigated when it turned out to not be her final design, though, and it's becoming less and less heard of after many posts that point out their differences, such as figure, facial structure, skin tone, etc.
Shipping: Running rampant due to no canon couples. Hiro and Honey are particularly popular in this field.
They Changed It, Now It Sucks: In the original Marvel comics the movie is inspired by, the team was based in Tokyo and everyone was Japanese. Disney's decision to change most of the characters' races is the biggest point of controversy (only their names are still the same), and there's also the setting being moved from Tokyo to the entirely fictional hybrid city San Fransokyo.
Tough Act to Follow: Let's face facts here. No matter how good this movie will be, it'll still have Frozen's numbers to live up to.