The writing team has made characters much more jaded and cynical over the course of the last seasons so they can't tackle the same wholesome narratives that made season 1 so good. So instead they stick to TV references and tropes to fill in the blanks that made the show so good. They can't depict morty as rick's naive sidekick anymore since he's apparently "grown up" from the experience and now is more of an independent prick. In season 1 morty was you, the viewer. Each time you were thrown into those adventures with rick you were literally just like morty, being thrown into the episode to figure out what is going on. but now morty is by himself and you can no longer relate to him on the same level you did back in season one.
The second issue is the unbalanced portrayal of family's routine. In season one there was a strict grounded setup that resolved around boring daily activities - beth worrying about morty's education, Jerry helping morty with a science project, Summer finding a part time job. Now the show focuses too much on its twisted side and the amount of random scenes and characters is blown way too much out of the proportion.
Despite all the hardships and broken expectations, I still admire Rick and Morty for what it was. It may not be the same anymore but at least it was trully an inspiring gift, a combination of Justin's ingenious creativity and Dan's down to earth constructive storytelling.