I didn't love the ending because a little too Sopranos for me. The bad guys win again, with literally no consequences for the central family in the story. Ruth, like Sil and Bobby Baccala in the Sopranos, bites the dust for being too close to the sun. It was clever when the Sopranos did it, but that was 16 years ago.
The show did a good job of making the viewers want Wendy to die, and I don't think anyone would have been too upset if Marty didn't survive either.
I had to look up who Schafer was because I kept forgetting. That whole plot arc makes a lot more sense now.
Omar Navarro may have gotten the best death in the show. Elegant, respectful and realistic for a key character.
Some plot stretches:
Marty running the cartel was a little far fetched, but Jonah getting the jump on a Chicago cop was really ridiculous. There is no way a 15 year old nerd would have been able to do that.
I was a little disappointed in the CEO of the pharma being such a wimp. Someone in that position would be tougher in real life.
While Ruth could be insanely stubborn, she wasn't an idiot. She knew she would have to be looking over her shoulder the rest of her life when she killed Javi, so she should have been tougher to kill. And while Javi's death was credible, Javi should have never been able to get to Darlene so easy, so I guess in Ozark world crime bosses just wander around without any security.
Ruth should have had some plot armor from the fact that Camila had just appeared in a room with roof and the FBI. The FBI would unleash a whirlwind of pain on the cartel if the money launderer/CI was killed the day they FBI put her in the field. The writers should have either not put Ruth in that room or explain why she can be killed anyway. It feels like a plot hole otherwise.