Making him more like a "real" Clark would have made the movie worse for me.
Superman Returns was in the tradition of the Donner movies. In contrast to L&C, where the guy without suit and glasses is Clark without glasses, I always had the feeling that the movie guy without the suit and the glasses would be Superman without his suit.
That's also a problem I have with quite a few of the movie fics. Quite often they aren't Superman (movieverse) but Lois and Clark (TV series) in a movieverse disguise, some even liberally sprinkling the L&C stock quotes in (for example, Clark is who I am, Superman is what I do).
I find both takes on Superman/Clark interesting and was quite happy with Routh's Superman and Clark.
I remain skeptic about the Nolan thing and the apparent trend in Hollywood to make everything "dark, cool and edgy".
