We need a real villain please

Zod, not a bad choice. No spandex please

Brainiac is a good idea, Zod could work too. But there needs to be build up. Superman has been fighting heros for a while, you are not going to turn up and win in a fight day one.  Remember the scene from DC Universe?

Perhaps Lex’s involvement could be explored here – helping the villain, controlling opportunities to create chaos would allow him to bet against the market making billions.