As I mentioned yesterday, I felt like there were great moments, but a lot of it felt like "filler". I think either they should have told the same stories in half as many episodes, or made sure they had enough to keep things moving through the entire season.
Beyond that I think my biggest problem was related to the character's powers. All the characters have some pretty cool abilities, but other than Daredevil, they rarely seem to use them and the writers generally didn't give us villains that could match those powers and require them to use them.
I found that particularly glaring in "The Defenders", in which it seemed like super-strong and indestructible Luke Cage shouldn't have had any problems with a few ninjas. In the fight scenes I wondered why everybody didn't just hide behind Luke and let him handle it.
And I suspect many of us had the same annoyance I did with Iron Fist - in the first season, it seemed like he never had the ability to use his fist. He'd be fighting punks and I'd be screaming "Use your fist!", but he rarely did (and if he did, those punks wouldn't have even been a challenge). And then the second season came around and he didn't have the fist through most of it.
I suspect most of my biggest issues - stories that moved slowly, lack of powered opponents and lack of power-use by heroes - were budget related. Doing the things I wanted to see would have cost more money.
But my feeling is: If you've got super-powered characters, write stories in ways that have them using their powers to fight challenging foes. And if you can't afford to do that, don't use characters who have powers.
