Clark is "real". He is a real guy, with real feelings, emotions, and...
hat hair.

Sorry, DJ, couldn't resist.
Might make an interesting story if he had flown in and offered himself to her as Superman.
There is a great story addressing this by MLT, Midnight Gambit. Although it's not at the point of proposal, instead it's right before the wedding.
It always irritated me that Clark didn't take those extra steps in the show. Either have Superman tell Lois his suspicions about Luthor or just come clean about his identity. Either one probably would have been effective in stopping the wedding, so the fact that he did neither says to me that his love for Lois had limits. He was willing to allow her to marry Luthor instead of exposing himself. But when Lois decided she loved Clark, her love had no limits. She risked her very life to save his parents. To me, that is a very interesting and telling contrast.
In contrast to the L&C superman this guy is perfectly comfortable with Lois choosing him for his powers.
Yes, but in the movies I always get the impression that he views himself as Superman first and CK second instead of the other way around. That irritates me to no end, but it does make this understandable. His powers are who he is.
What makes Superman Returns great to me is Brandon's Superman and the special effects. I found KB not only to be horribly miscast as Lois (she looks all of 16 years old!),
I agree.
Superman's reply was merely an observation about the difference between Richard's flying capabilities and his--I didn't hear anything malicious in it at all.
Well, I didn't hear malicious, but I did hear sly. And I can't blame the guy for pointing out certain advantages.
I guess the only thing that bothered me about SR and Jason was that Clark didn't come clean with Lois at the end. If he is going to be a father, then his Clark persona is going to have to come into play. But, as I mentioned above, part of the problem is that he doesn't view Clark as his real self, which leads to a very unsatisfying situation for me. This would not have been a problem in L&C, which is why I loved the show. Clark was Clark. Superman was an outfit.