An aspect of Luthor I enjoy that Snyder missed completely by casting Eisenberg is his obsession with the advancement of humanity and how Lex feels he's at the forefront of human evolution. I want a Luthor that has a dominating presence, who is intellectually ferocious, and full of pride for both his mind and body. Basically, I wanted All Star Superman Luthor 😛. Not all versions of the character are portrayed this way, and neither Hackman or Spacey fit that bill, but it's what I wanted to see this time around.
They should have cast Mark Strong as Luthor. I want that guy for everything though haha