I feel like it really went downhill in season 3, there's just not really any clear objective anymore to root for the main characters to achieve.
In season 1 it's all about setting up the businesses to launder the 8 million. In season 2 it's about getting the casino. Season 3 it's not particularly very clear and they just become a really annoying squabbling couple constantly undermining and backstabbing each other. The Ben stuff was quite powerful but ultimately I don't really see what the point of him was, nor did I like how he became a love interest for Ruth who to this point has been completely her own person and mostly desexualised, and was a better character for it.
I also agree with a previous post about how it's ridiculous how many people know. Maybe I'm not the most well-versed in legal stuff but come season 3 how the FBI don't have enough on them to shut them down seems ludicrous, they're constantly around and they know exactly what's going on but don't really do anything about it. At least in earlier seasons you had agent Petty just mostly working on his own and it created tension as to whether there would be an incriminating slip-up which would have consequences, and you'd be on the edge of your seat during those conversations he was listening in on wondering if he would get something. Now they've got this huge operation and just do nothing and it amazes me how Marty and Wendy have created the "brand" when it's so obvious what they are and the FBI know so much that at least some of that stuff should be out in the public circulating as rumours which wouldn't make it possible for them to host these functions and starting charities.
They seem untouchable now and it takes away a lot of the tension and actions don't seem to have consequence. What made Breaking Bad so great was how secretive Walt had to be and how everything he did would have consequences and the smallest slip up could get him in trouble or risk his family finding out at least. It was also much more interesting having Hank being on Walt's trail and trying to find out who Heisenberg actually was, than this where the law enforcement know all about who they are and exactly what they're doing but never seem to do anything about it apart from that one time they raided the house. While I'm here I'll throw in a Game of Thrones later seasons dig as well, character actions just didn't have consequences anymore, unlike in the earlier seasons.