The issue with the first seasons (which is quite short from memory) is that they make Leslie a figure of derision. Once they pivot and make her this incredible source of optimism and hope - someone the rest of the main characters respect massively, even if she drives them nuts - it changes the dynamic of the show completely.
It's been a long time since I watched, but there is a point in Season 2 when it just clicks and then becomes so, so good. It really hits its groove when Adam Scott and Rob Lowe join the show, but it's very good before then too.
I actually think it's still pretty strong towards the end of the run, but like most sitcoms there's just a point where it's diminishing returns and the time comes to end it.
Also has an insane amount of depth in terms of supporting characters. Saw it compared once to a live-action Simpsons in that regard and I get the comparison... so many funny minor recurring characters who round out Pawnee.
