There ain't alot of option. You either crop the image to the width of 360, and you'll lose a bit in height.
Or you crop the image to the height, and you'll leave some blank space in width. The only solution to that is extend the image somehow.
See here, six limbed Smaug! At first I wanted him to be like this but I prefer the four limbed Smaug, makes him much more snake like and is more practical for the flying.
I really dig that Cumberbatch was mo-capped for this. I know not so much for the movement but for himself and his voice. Really really great that they used mo-cap for his face mostly to bring Smaug to life. I LOVE Smaug
IFwe ever get films of The Silmarillion, Glaurung is gonna be fantastic as well if also done with mo-cap! He's got no wings, he's not larger than Smaug but damn was he awesome in the book!
But, Christopher Tolkien is pretty old now, it could be done any moment.
Yes that sounded cold. But it's true.
I know the estate won't sell it to WB anytime soon but you never know. Like I said, IF it ever happens and WB wants PJ to direct (of course) then I think PJ could get a lot more time for script work and pre-production than with The Hobbit. It shows in the finished product. And of course, The Silmarillion is probably one of the hardest books to adapt for the live screen.