Darkseid has potencial, had potencial, but the finale ruined him, i think Brainiac was good.
The first seasons had a lot of flaws too, the first flaws began when there were too many freak of the week episodes, it became too much of a coincidence for them only to appear then and for them allways targeting the same people.
Then they tried to correct it by focusing more on Lionel Luthor, the problem is that Lionel changed his personalitites too many times, from blind, to a saint, then he was bad again, then he wasn't, then he was a good guy and died as a good guy, then he was in fact Oliver's parents killer, then he was remember with disdain by Clark and his other universe version ends up becoming the last Lionel appearance.
I think a major problem is that they forgot or rushed some elements and characters, for example, remember Lana's friend that died? The one that reapeared as a clone in season 1 or 2 as a little girl? I tought it was a predecessor for Bizarro, it made sence, but they ended up aging her and making a completelly diferent Bizarro from what i was expecting.
Nothing of what i said is supposed to be insulting for the show as i liked it a lot, but it sure had a lot of problems