I don't think so.

I'd say Mermaid is pretty close :)

It seems that with the classic princesses the side characters are more developed and the princess has the least development. Whereas in the modern films it's the reverse: the focus is on the princess and her prince (or mom, or sister) and the side characters are just there to move the plot along.

TLM and SB.

Yeah, a few.

Mulan, Aladdin, Tangled and TPATF all come really close in my opinion. All had characters I always found interesting and developed. =)
SWATSD- their are a lot of characters there just to push the story along that we know nothing about (Huntsman, Magic mirror)
Cinderella- is definitely not developed and I definitely find prince Charming bland. (Cindy has no reason to be developed though)
SB- I find Phillip bland and Aurora to be the same through the whole movie.
TLM- Ariel is completely undeveloped and I find Eric incredibly bland.
BATB-It comes close, but the characters tend to sometimes be boring, and ugh Gaston...
Pocahontas-Hate to admit it, both the characters can be seriously dull sometimes.
Brave- The guys stand around in the movie and do absolutely NOTHING!
Frozen- I find Anna and Elsa to be both very developed and interesting or complex characters in their movie. The duke and Olaf are definitely not.

Aladdin and probably Mulan.

Sleeping Beauty.

Batb and aladdin.

Aladdin and The Princess and the Frog, in my opinion

What Sk8er_grl said.
I'd put my money on Aladdin and Mulan.

Anna is kind of annoying and way too bubbly, Elsa could've been developed better, Kristoff is cute but nothing special, Olaf is laughably stupid, Sven is just kind of there, the trolls are annoying when they automatically assume that Kristoff and Anna MUST be a thing, and Hans sends god awful messages about feminism.





Oh, and none of the others have perfect characters either.

"Beauty and the Beast..."

Beauty and The Beast.
Mulan and Aladdin maybe.

Mulan maybe, or Beauty and the Beast.