Looks great. Not sure if you were planning on ending the Burton/mlp here but if you were to do more in the future I'd like to suggest: princess Celestia,luna,cadence,prince blueblood,and shining armor.
Even more of this is awesome! I like the fact that Derpy's cutie mark is made of spirals (a trait of Tim Burton art) rather than bubbles, and how Lyra apparently grafted a HUMAN HAND over her hoof (and her eyes are yellow, showing a certain degree of ill health, most certainly psychological), and how Octavia's cello has spider-legs at the base of the neck, and NightMare Moon's forelegs ending in spikes rather than hooves, and Zecora's jagged edges to her cutie mark! (Did Derpy have her left hind leg replaced? Because it's stitched up at the hem of the "sock".)
Will we be seeing more of this of more characters?