He looks too evil and he always get bad guy roles. I'd like Lex to look like a man who is able for the best and the worst, an ambiguous character, a good man who fell because he got obsessed and afraid and consumed by his own demons. That guy's face screams "i'm evil".
While we got too much Lex in the movies so far, i'd love to see them adapt the modern Lex and explore his character. Unlike the Joker he doesnt get locked up, he's always there, escaping the law, plotting his next scheme, manipulating villains and the goverment. The icing on the cake would be if he redeems himself at the end of all the movies, like he supposedly does at the end of All-Star Superman if you are into this whole [blackout]Lex = Leo Quintum[/blackout] thing. So yeah, i'd like a deeper Lex, a human Lex, not a carricature, or a downright evil dude.