If Tom Cruise is Lex, he should totally play it straight, with this evil undertone.. a narcissist.. I don't want super suits, or tech... I just want his brain being his weapon v Superman.. setting clark up to fail, with mind games and double jeopardy. Getting other nations to fear Superman, getting the people to be afraid.. setting him up to fail.. Tom would nail this.
However... I don't care what people say, Billy Zane is my Lex Luthor, all day every day.. he would own it so well and be cheap.
For superman, it's tough... I kinda wanna go a totally different route, look wise... I want this big, buff farm dude... so when he is Clark, he really has to reel it in, put on an act... Superman for all seasons style. I know it's not the easiest to translate on screen, but like a young Patrick Warburton - here he is at 37 - prime Superman age.
So he would need to wear baggy clothes, keep a low profile... blend into the back ground.. Then his Superman, for me, his Superman needs to be proud, almost cheesy.. like too nice... think of Chris Reeve superman turning up at his son's birthday party, knowing if the kids weren't happy he loses custody lol, that kinda nice....
Lois works out pretty quick, but plays along for his sake... it's almost like it's an unwritten rule... that she dates Kal El, not clark in the office.. like, the acting has to be great, but there is something in Lois's eye at times, that lets Clark the office version know she isn't dumb, but is helping him, less is more.
I would have the classic suit.. bright.. colourful.. just make this character larger than life and he doesn't care at all... he just rises above anything and is just so cool and respected... like, he is down town and in an area say like the hood or whatever but he treats people so well and relates, that like, even a petty thug he stops, can't help but respect him..