I think you're missing the point here. The creator of Merida designed here after a real person and didn't follow the standard Disney way of how a princess looks like. Now Disney gives here a makeover and thereby removes some of the attributes that the character and the movie was about. If I were in the position of the Merida creator I would be upset as well.

I also have 2 daughters who are big fans of the Disney princesses, but I would very much like it if they at least had the option to chose a princess that doesn't follow the standard formula of the previous 10 Disney princesses.