That's a great question! I don't know that Stern had any kind of radical character progression in mind, he just had a really great feel for Peter Parker and his world. He 'got' the characters and what makes them tick.
My favorite Roger Stern Spider-Man story is a done in one, ASM #246 ("The Daydreamers"). Felicia, MJ, Jonah and Peter all get a poignant character moment, courtesy of a peek inside their daydreams.
While Scott does prefer the marriage (as do I), I think you took the second part of his statement way too seriously. He was clearly just having some fun with that line!