The devil is in the details. I ALWAYS think that cosplay is a 3-dimensional multimedia experience/work of art. This is always why cosplay videos seems to better display quality cosplay work better than just still photos. Though to be honest, I even have certain soundtracks blasting around me when I'm in cosplay (usually the character's theme or songs).
If you see most pics of Rarity's outfit, you will notice strips of back coverings that resemble wings to further adorn her Morning Dew and Gossamer wings. Even though it was not necessary, I decided to spend 1/3 of my budget on this to make them.
They are made of silk and satin with wiring and thick foam interfacing inside to allow custom forming and it is detachable via suspender snaps.
The result? One of them most... if not the current (Summer 2013) most accurate interpretation of Rarity's final outfit for that episode.