@Daeus-lamb good analysis. I think I caught a few deeper, better hidden symbolic threads, but I also think I was a little more familiar with the myth it was taken from than you were. I haven’t studied it (at this point, don’t intend to :P) but I know the basic structure/storyline.
For a story like that, I think the whole symbolic weight just rests on pulling it off in a way that capitalizes on all the thematic moments of the original myth, while deepening them and delving into implications the original myth didn’t touch on. That myth has been around forever (and, at least in Lewis’s time, was a big staple of a classical education, along with all the other Greek myths) and is very much a part of the general consciousness, so in a sense it itself is already one giant symbol.
INFP-A. If you can't be brilliant, odd will do.