Welp, this is going to be a big project.
ANYWAYS, my base body is the molded Celestia with a Fluttershy head. The reason why I chose this was because of how thin the body was in comparison to the Brushable Celestia. I used a normal pony head because the Celestia head that came with the molded Celestia, simply put, IS WAAAAAY too small.
I trimmed off a bit of the hooves, just enough for the notches and holes and sculpted the rest of the hoof in Milliput, extending her height. From the screencaps I figured Chrysalis is a bit taller than Celestia and was about a head taller than Shining Armour so I used them as measurements.
There's still a very long way to go though.