Did the producers ever think about spinning off Colonel Flagg into his own show? The episodes with him were always good, I think it would have done better than Aftermash.

I'm pretty sure they didn't.

Colonel Flagg was a great character and Edward Winter did an excellent job of portraying him however I think he is a character best taken in small doses. The once or twice a year that he visited the 4077th were just right. I don't think Colonel Flagg is a character you would want to watch on a weekly basis. He is just too one dimensional of a character.

I think it would've worked.
Look at The Andy Griffith Show spinning off Gomer Pyle.
And Mary Tyler Moore's Rhoda, Phyllis and Lou Grant.
Cheers and Frasier...

good character but not enough to support a whole show.

The problem I see is that while Flagg is a very funny character, he isn't likeable. You'd want your sitcom lead to be likeable, I would think.

It wouldn't be so different from Get Smart.