My chief problem with "Rick & Morty", aside from the producers being assholes as it turns out, is that the show seemed like the same joke over and over again. Watch Rick be a self-loathing drunk! Again! Watch him crush Morty's illusions! Again! Watch Morty's family be rubbish! Again! But I admit I've only seen scattered episodes in the first two seasons and never sat down to really watch the show. Mostly I watched it over my girlfriend's shoulder, so to speak. The ending of the 2nd season intrigued me because it suggested growth but my guess is that it worked out much the same as all the attempts at developing Greg House. Whatever happened, he never grew up.
@kara_dreamer In fact, you are describing the "problem" of many series where the only link between the episodes are the evolutions of the characters (nearly all police and detective series, Malcolm in the middle, How I met your mother, TBBT, I don't know, many series…).
But yeah, in Rick and Morty there is an evolution. Characters evolve. Rick is still an A-hole but not the same one he was at the beginning, Morty is still crushed but he's much more rational, realistic, cynical. The family evolves too.
I had a different feeling at the end of the S3 than the one I had at the end of the S1 or S2. And I feel every episode is adding something to the serie IMO.