It cratered when Hunnicunt showed up. What a tart. And Henry Morgan.He was ok but not nearly as good as that guy from Bloomington. And that gay priest guy- pfft. Winchester was OK.
In the early days, Alan Alda got a lot of shit from the women's movement for his macho advances on the babes.. So they toned it down. Some of the early scenes between Frank and Houlihan were hilarious.
MASH got better as it replaced one dimensional characters. Trapper John, Henry Blake, Frank Burns.......replaced by BJ Honneycutt, Col Potter, and Charles Winchester III. All provided for deeper stories.
The only loss that really hurt was Radar and getting Klinger out of the dress helped. Also, Hot Lips became a better character in later seasons