well, for me, having Lex know young clark from Smallville makes their rivalry more interesting and sad. I also like the idea where Lex actually LIKES Clark, even though he hates Superman. Kind of the opposite relation Supes has with Lois ( she likes Supes, doesn't care much for Clark ).
but you can always go a different route. For example, there could be dialogue/scene where Lex describes how he came out of poverty in Suicide Slums and rose to power. As long as it contrasts Lex's character, upbringing, and motivation with Clark/Superman's.
also, another thing I would add to my story would be Lex stealing some of the Kryptonian technology for himself. This would obviously set up Lex's plot for the sequel, perhaps using the alien technology to create "advanced alien weapons" and a worthy villian to take down Supes. Such as Metallo, or Brainiac, or even Doomsday.
Doomsday, for example, could have elements of Bizarro/Nuclear Man in him. Now, I wouldn't want Doomsday talking backwards or anything.
I would make him essentially a cloning experiment gone bad. That is, Lex, through a front such as Cadmus labs, tries to create a Superman "clone" or equal to kill Supes, combining Superman's DNA, Kryptonite, and Kryptonian technology. The experiment, however, is imperfect, and the hulking monstrosity called Doomsday results........
that's just an idea......but the point being that Lex actually makes offensive use of Kryptonian technology, something he didn't do in SR.