Both AMC and Sundance have been showing MASH lately, with Sundance doing a recent 48 hour marathon. Re-watching many of these episodes has reaffirmed what I've always believed, which was that Charles is a really great character. I loved Frank Burns, but he was a one trick pony. There wasn't anything else they could have done with him, which of course led to Larry Linville leaving the show. There was no room for growth or sympathy with Frank, and had he stayed, the character would have dragged the show down.
Charles, on the other hand, was brilliant. Yes, even up until the end he was a narcissist, a boor, and had a superiority complex. But then we get some truly moving moments with the man. The episode where threatens the CO of a man with a stutter, only to find out his sister is a stutterer. The Christmas episode where he gives the candy to the orphanage. The moment between Charles and Hawkeye where he tells him that "where I had a father, you had a dad". And even in the finale when he shows his pain at the death of the musician. And let's not forget his first appearance, when he sneaks the snake that Hawk and BJ put in his bed back into Hawkeye's. No matter how bad those two dished it out, he could always give it right back.