I enjoyed it. Overall was it as good as Breaking Bad? No, but that doesn't mean it wasn't great and its the closest we've had to a Breaking Bad-type show. Some criticisms I have seen:
Jumping the shark - to be honest I think every show does this. Breaking Bad did it to an extent with Walt's A-Team robot machine-gun attack. Ozark did it with:
Spoiler
Marty becoming cartel boss, briefly
But it's not egregious and didn't ruin the show for me and if anything its a bit of fan-service. Game of Thrones jumped the shark, landed in a plane and flew off into fucking outer-space for example.
On the other hand (Ruth):
Spoiler
Ruth's death was inevitible and had she lived happily ever after despite the cartel boss knowing she killed her son, THAT would have been GoT-level bullshit. She was the best character on the show but she made her decisions and as soon as she shot Javi she was doomed. The flashback scene at her trailer about 20 mins before the end should have warned anyone what was coming.
Regarding the ending:
Spoiler
It felt slightly rushed but it worked for me. It showed that money/power do trump good-will (from the detective) and that Jonah was finally corrupted by Wendy/Marty. I'm just surprised that it has actually left room for a spin-off or follow-up in years to come for sure. Netflix hedging their bets I guess.
It's so hard to get the ending of a long show correct. Some Soprano's fans still don't like it's ending (I do), Breaking Bad's was decent, GoT & Dexter horrific. The two best I can think of are Mad Men and Six Feet Under. To me this ending is on a similar level to Soprano's or Breaking Bad - not earth-shaterring but satisfactory.