I've watched all but the final two episodes of season 2.
I didn't really follow Luke Cage in the comics, so I don't know much about his Rogues Gallery. But I dig the spin on The Serpent Society, and wonder if we'll ever see more. They set up a cliffhanger at the end of S1 with Diamondback and the Seagate scientist who "created" Luke, but I'd much rather see a more compelling villain, rather than just the Near Identical to Cage type super villain that Bushmaster is, and that Diamondback was set up to be.
Mariah is a good villain, of the type you love to hate, but she isn't really any kind of threat, at least where I am in the series. Unlike the Purple Man in JJ S1, he was spectacular. Mariah just doesn't have the same vibe. Frank Castle would have already splattered her across the wall.
Danny's appearance in LC S2 is much more palatable than his own series.
Loving Misty, she could support her own series.
Hope to finish the series this weekend.