Byrne did some bad things in postcrisis. He made Krypton a 1980s dystopia. He tried to give Superman's powers logical explanations.
But he wrote a humanity into Clark that was only equaled by Elliot S! Maggin, and he gave us Ma and Pa Kent as living people. And for that alone, I think him.
That he pulled Clark and Lois out of their 1960s hide and go stupid dickery... that's a miracle.