See, I find the opposite to be true. Parks and Rec tends to be hit-or-miss with some of their episodes. Plus, I don't find the characters as appealing as AD. Parks and Rec has characters like Ann and Ben who play it straight and tend to bring down the mood of most of their scenes, as well as characters who just seem 2-dimensional (Ron, Jerry, Mark from the first season, Aziz's character whose name I forget, etc)...however, I think Leslie Knope is a great character. The characters from AD (with the exception a few) are dynamic, and you learn a lot about them as they grow and develop as people as the series progresses, whereas it seems Parks and Rec establishes characters the moment they're introduced and then just puts them in various comedic situations.
You say that AD's humor is subtle, and I half agree. I think a better term would be "layered". Almost every joke in Arrested Development builds upon the one that came before it, which leads to a lot of meta joke-within-a-joke moments and callbacks to previous episodes (sometimes even previous seasons). On one hand I can see why this approach would alienate some people, but the upside is that you can watch an episode a dozen times and still find jokes and references that you missed in a previous viewing, which is a sign of really great writing. Parks and Rec doesn't have that - while I can re-watch P&R episodes and still be entertained by them, I don't get that sense of "Oh! I totally missed that before!" as much with P&R as I do with AD, which happens almost every time I re-watch an episode.
That being said, P&R is probably the best network comedy around right now even if it is (imo) on the downswing from a few years ago.