Ihope you like how it turned out! I'm rather happy with it myself^^
I kept the hair and shoes like you asked, though I made them more metalic. WHat I did with the dress was pretty simple:
I reshaped it to fit the body shape of the pony, changed the color to midnight blue (It looks like velvet to me^^)
I also revamped the color and removed some ribbons. I added some gold to the lace as well.