Betsy Blair's too good looking
I think this is a nice movie with a good message. But having been something of a Marty myself over my life, I thought Betsy Blair was a bit too good looking for the role. I suppose she had to be: Hollywood wouldn't tolerate a really plain-looking woman in such a leading role. It would take a John Waters film of the 70's and 80's for that (say, Polyester).
When Marty says to her "you're not such a dog," I half expected her to say, "But you are." That's probably the reality for most men like Marty in this world.
It's wonderful that he got a break and met a wonderful person like her, by being kind and decent. But you can't count on that.
"Extremism in the pursuit of moderation is no vice."