I have actually played with that pattern before and can suggest using the front of C and the back of E. I would say use extra reinforcing along the sides and top to help it keep it shape and then instead of lacing it you could use the straps on the side to hold it together. I would say make a draft out of cheep fabric first and see if you like how it fits and you can fuss with it. Might sound like more work but it will save you tears later...
I can link you to the one I made off this pattern once I find all the photos.
Anime NebrasKon 2015: Staff Shirt of AMAZING
Therru/ Tales from Earthsea
Thor Dress/ Thor Marvel Universe