When I was introduced to Chaplin's films...oh, so many years ago...actually, it was only about 9 years ago...but whatever...anywho...I watched City Lights first followed by Modern Times and at that time, I liked Modern Times better. But over the years, they've changed places and I consider City Lights the best Chaplin film of all followed by Modern Times, Gold Rush, The Dictator, The Circus, The Kid and then Limelight. Everything else after that.
Modern Times is my favorite Chaplin film, but City Lights is a CLOSE second. But I still consider City Lights his best film because it best represents Chaplin's perfect amalgamation of comedy and pathos within a silent medium(Modern Times is a mute sound film). I think their flow is about equal because they feel like four 20 minute shorts within one film with a certain plot line. However, they are both within my top 6 favorite films, and everyone can watch them. In fact, when I convinced my friends to watch Modern Times, I was surrounded by people 12-18 years old, and they all laughed HARD at the feeding machine scene. I also have to say that the Circus is Chaplin's most underrated films, I mean, it does have the best banana peel gag of all time.
I think City Lights is probably the greatest silent film of all time. It's a rare perfect film, and it probably has the best ending of ANY film ever made. It is a simple film though not that that's a bad thing. With Modern Times, he managed to make a much more complex film 99% as good as City Lights, and that is saying something IMO. I did not like Modern Times' slapstick as much as other Chaplin greats. It just wasn't quite as funny. It had it's moments of course, but it was too uneven. I still give it a 9/10. I agree though about Paulette Goddard. She was a breath of fresh air and easily the best lead actress in any "silent" movie.