I'm flexible on the red hair and freckles - I just used that as an example. Still, CK would be slightly built, about 5'8", very fine features - I see him with a hawk-like nose and a bit of a weak chin, blond hair. Maybe grey eyes. Remember his character would still be the same as L & C CK/S though. So how does that sound?
But one's body and looks does effect personality. A slightly built man with fine features will have different experiences than a man four to five inches taller.
These differences will color his outlook. He won't have as imposing a demeanor as Superman. It will be harder for him to impress people and harder for him to prove himself.
A shorter Clark will likely be more intense as he needs that edge to get through to people. He has to push harder simply due to being shorter.
I would liken it to dog sizes - German Shepherds and collies are medium-large. They are smart and (depending on the personality) don't need to bark much unless trained to - they have enough size to do what they need to do. A Saint Bernard - ditto. All the Saint Bernards I've known were gentle giants.
Terriers on the other hand - their size works against them and they compensate with loudness and snarkiness.
I can see Lois as a terrier. Dean Cain's Clark is definitely a German Shepherd and Brandon Routh's Clark is a Saint Bernhard or Afghan Hound. (Put away the breakables, Clark is here.)
:p
