Yeah, and like the Joker the way to go if Zod appears again is to make the character substantially different from the earlier screen iteration.
Which should be easy, since the version of Zod in Superman II had very, very little in common with his comic-book namesake. The original General Zod was a military officer who was a major player in Krypton's space program, and when that program was abandoned following a disaster, he felt betrayed and sought to overthrow what he saw (correctly, as it turned out) as a dangerously short-sighted government. He was something of a Nazi-ish figure, a militant Kryptonian supremacist, but somewhat sympathetic nonetheless. And there have been a variety of different interpretations of Zod in more recent comics as well as in Smallville (though Smallville's version in its 9th season had a number of points in common with the Silver Age Zod -- military leader, somewhat sympathetic, convinced of Kryptonian supremacy).