A lot of films and tv shows have this issue where it takes too long for them to introduce a villain that can match the hero in either physicality or intelligence. By the time they introduce a villain who fits either of those attributes, it weakens the plot of the story because they’ve wasted so much time building up. Jessica Jones Season 2 suffered from this a lot because we don’t have a villain who matches Jessica in either of those.

Cottonmouth was a great villain but he never felt like an legitimate threat to Luke at any point. Even when he told Luke that he would blackmail him by sending him back to Seagate, he still didn’t feel that threatening. Mariah was a threat to Luke because even though she would’ve been squashed physicality wise, she stayed ten steps ahead and he also knew that he couldn’t lay a finger on her.

Sure, Diamondback was corny with how he quoted Bible verses every other scene and he wasn’t on the level of Bushmaster in Season 2, but at least he felt like a physical threat to Luke right from the jump when he nailed him with the Judas Bullet. If the final battle was a little more thought out, I think the second half of Season 1 wouldn’t have gotten so much backlash.