Welll,
As for Charles becoming King.... I have no problem with it and I think that Camillia meight get the title of Queen Consort or Princess Consort. I must admit Camilla is not my favorite person but she is too often judged on what happened prior to Diana's death and so I try to look at her as a woman who loved a man whom she could not marry because she was not 'fit' to be a member of the Royal Family. That is atleast how it appears she was judged in the 80's by those who knew of Charles' affair with her. As for Diana, she always will have a saintly image, and I must say I admire her very much for her good works and her warm-hearted appearance, that was her biggst charms - and she passed it on to her sons -, yet I must admit that Diana also had her faults. Yet, the mistakes she made are understandable because she was unaccepted by the Royal Family and turned out to be so different from them, therefore she wanted attention for her problems and she wanted the world to know that her marriage was not as happy as it was meant to be. I think that is one of the reasons why Charles, and especially the Royal Family, accept Camilla because she appears to be much more like them, unlike Diana who was as different from the Royal Family as day and night are from each other.
That does not mean I do not 'prefer' Diana because in my opinion she had all the good graces a Queen could have: good looks, charm & grace, style and a heart-warming appearance. After all that is what made her so loved, even up to this day. And as for Camilla, she is accepted by the people now, and even though Diana made bigger news, she is far closer to the Royal Family in her ways and acting then Diana was and therefore she will not get 'caught' in the eye of attention in the way Diana did.
Also I often like to compare the marriage of Charles & Diana to that of Emperor Franz Joseph of Austria and Empress Elisabeth 'Sisi' because both marriages started as fairytales and could have worked and ended happy if both partners would have understood each other better and would have accepted each other better without trying to find other happiness... But when one is not happy in marriage one looks for happiness outside the marital bed, it happens all the time and will never change. Only these days people part much more often.