It seems like you have the one camp wanting Lois to be average looking, their argument geing that what makes Superman so great, because he doesn't fall in love with a woman for her looks, but her personality.
That can still be the case, although it doesn't matter if she really IS attractive, since Superman isn't falling in love with her for that reason.
Then there's the other camp who want Lois to just be as ***** hot as possible.
I get that Lois isn't just a hot piece of ass, she isn't one of Bruce Wayne or Tony Stark's half naked bimbos, and pretty much everyone knows that.
But there's nothing wrong with her being attractive, like alot of people have said, she has to catch the attention of men like Lex Luthor and Bruce Wayne, she's not gonna do that looking like Plain Jane.
The sad truth is, from a guys point of view that the more gorgeous, or glamourous a girl is, the more stuck up and beauty obbsessed she seems to be. Lois is so not like that, she's the complete oppisite, in fact she was an oppionated tomboy for most of her teenage years, and we saw some of that in Smallville.
Lois' beauty is more subtle. She kinda covers herself up in businuess outfits to look more professional but you get the feeling if she wore a bikni she would be smoking hot. She just doesn't like to be seen that way.
What I'm trying to say is Lois can still be very attractive, but resents anyone thinking that's all there is to her. Hardly anyone thinks of Lois as 'just hot', they all think of her as the hard working, ambitious, witty, outspoken, independent woman she is.
And that obviously has to come across in her character onscreen and in the actress.
I know that Olivia Wilde resents the idea of just being known as 'the eye candy' which is why she likes being seen in strong roles. I think she'd be great in the part.