All in all, the show was awesome. The plot never slacked, every moment was tense. The characters were exquisitely done, and the acting was great. And yes it did lack a bit in the realism department, but really, that's not what we're here for.
An absolute masterpiece. The third season managed to bring together the elegant perfection of the first season, and the breadth and pace that showed through in the latter half of the second season, to create a fitting end for what is certainly one of the best shows of all time.
S1 was great fun. S2, even better...then S3 came along and let us all down. The characters were often downright annoying (when did Hopper and Mike become such a-holes?). The plot, mediocre and cliche (I mean, really, Russians?). And overall the show felt like it was riding on the popularity of the first two seasons more than it was actually creating any quality in of itself (for example Robins big reveal in the last episode felt shoehorned in last minute for the sake of "diversity" rather than taking the time to actually do a good job of it).
Another super fun season, and though many would disagree I think that it is actually better than S1. Lemme explain, I felt that though season one was quality overall, something was lacking in the characters. For S2 though, I felt the problem was fixed, the characters felt more human and fleshed out, and they all felt purposeful, something I feel was not always there in S1, especially for the high schoolers.
Controversial opinion here, but I found the first season to be better, this should in no way detracts from the greatness of this season, S1 was just a really hard thing to follow. Some explanation here, I loved season 1, but season 2 started off on the wrong foot for me, though I'm not sure exactly why. I see why people feel the characters became more likable this season, but it simply wasn't as faultless for me, I felt the first few episodes could have been better. Though I will admit, around episode 6 onwards it gets much better, hitting the sweet spot again.
Absolutely amazing, no, really. The acting, amazing. The cinematography, amazing. The plot, amazing. The soundtrack, super amazing. The casting, supreme (you'll get what I mean if you watch it). Was it a slow burn, yeah, was it immensely complicated, yeah, but man was it worth it. If you couldn't tell already, I love this show, Every moment felt intentional and deliberate, no instance went to waste. I've purposely shied from sharing anything of the story because you need to experience it yourself, just watch it and tell me I'm wrong.