This is interesting. Maybe, instead of being executed, Cersei's prison sentence will leave her maimed or disfigured as punishment by the High Septon, which would parallel Jaime's maiming. It would be interesting to see how the two of them deal with the maiming in their own ways. Jaime, so far, seems to be becoming a better man for his injury, but I agree it could be the undoing of Cersei.
I like the emphasis you've made on her losing "all" she holds dear. Cersei values her looks and their effect on males highly. She often thinks about how she can use sex to twist men around her finger, and it's sad in a way that she thinks this is the only power she can have as a woman. But I would love to read about a Cersei scarred and burned (like the way Loras is alleged to be, and, sidenote, I wonder how that pretty boy will deal with the loss of his looks). I just don't think Cersei has it in her to recover from something like that.