On before telling her he was Superman because he needed to know if she loved the ordinary man. I think this is wrong on so many levels. I know he tried to tell her before, and the proposal might have been an impulse, but I didn't like it.
First, if he didn't believe she loved him he shouldn't ask her to marry him, otherwise the proposal would be simply a test and shows he doesn't trust her and won't be honest with the woman he loves and wants to spend the rest of his life with. Second, how can he ask her to marry him without telling her exactly where she is getting into, after all, he is Superman and Lois would be part of the secret.
This probably have been asked before, but if Lois wasn't so infatuated with Superman and had treated Clark better, would he have told her his secret sooner or at least before he proposed to her?
Ingra