It might change because I think they all have such flawless features, it's hard to choose.

It's a tie between of her eyes and hair...and her smile :D Aurora's just too perfect for some reason ...

I think they're best features are...

Belle's hair,
Ariel's hair/ mermaid tail
Pocahontas's hair
Cinderella's eyes
Jasmine's lips/smile
Mulan's lips
Rapunzel's eyes/ hair
Snow White's lips
Tiana's dimples/ smile/lips

It's the only one, we agree on....I think that
Snow White has the best lips
Cinderella the most beautiful smile
Aurora the best hair
Ariel the best expression in her eyes
Belle the best eyes (shape, colour aso)
Jasmine the best lashes (well, actually, the best movement of them, but there is no word in english for it)
Pocahontas the best legs
Mulan the best movement (though Aurora is more graceful)
Tiana the best curves
And Rapunzel has the cutest frekles

And Jasmine's eyes and Aurora's smile.

also Cinderella's eyes and Belle's lips, lovely <3

Absolutely

The only one we agree on really.

This and Ariel's smile, mostly. There are a few others I agree with too, but not as strongly.