Leaving aside the characterisations (it's not hard, the ones making the movie did too) the major "heroic moment" comes early in the film when he saves the plane. The grand finale of the movie is Superman's epic struggle with a piece of geography.
Spacey's Luthor was far too much of a nod to Gene Hackman's, and just doesn't being to compare to the Luthor's we've seen since then in comics and other media, from John Shea to Michael Rosenbaum, with a tip of the hat to Clancy Brown.