They had episodes like 'Dead Dad', 'Dear Uncle Abdul' and 'Dear Peggy' where Hawkeye, BJ, Radar, Klinger etc. narrated the camp's events through their voiceovers when writing a letter. Frank doing it may have been a bit extreme but an episode like that with Margaret might have been interesting.
Even fave Sidney Freeman got to narrate an episode through a letter to Sigmund Freud.
See, Unc, it's no wonder I never got a Section Eight. There's nothing special about me - everybody here is crazy.
I could see an episode where Frank writes a letter to his wife and then exaggerates everything to make himself look good, like in the 'Novocaine Mutiny' episode.
It was one of those days that, more than most reminds us that war, however much we may enjoy it, is no strawberry festival.
Frank: - I suspect that there was little love in Frank's marriage. It was a marriage of convience for Frank. A single doctor, in the 1940s, was ultra rare. She was also a major tax write-off. The house and car were in her name so his insurance, mortgage, and more were probably a lot lower, since his salary would make all that higher.
He was married for the image of being married. The home movie of his marriage shows that she, as well, wasn't likely deeply in love and was rather ordinary looking, She may have felt that he may have been her only option.
Margaret - Being military, she didn't write her dad because she probably saw her duties at the 4077th as her duty with little there worthy of writing home. Little, aside from a bit of her non-military duties, were worty of note to a military veteran of several wars.
You also saw just how critical her father was of everything. I suspect Margaret might have felt that he would have been unhappy with her relationship with Frank, poker games, drinking, and more.
Remember how her father felt about Hawkeye and B.J's attire and attitude. If she'd written about their antics, especially the womanizing, he would probably have given her grief about the nurses, and more.
Destroying an empire to win a war is no victory and ending a battle to save an empire is no defeat
They could have done a split episode where Margaret writes a letter to her father trying to make him proud of her, then write her mother saying how sad she was and how difficult a time she had.
The closest we got to Frank writing a letter was in a phone call to his wife and later on in another episode to his mother. He lied and was deceitful to his wife when he convinced her not to divorce after she found out about Margaret. (She looks like an old army mule. With bosoms. LMAO!) Truthful to his mom at having a hard time there.
I could see his letters going either way. But it would be interesting if it was honest just like how everyone else is.
I think what would have worked best for Frank would be a letter to his mother. I think it would have been a great look into Frank Burns' mind if they had an episode where Frank writes a rosy letter to his Mom while we see how the world really treats him.