My brain hurts considering the question. I love both. Community can get so goofy that it is often hit-or-miss. Granted, it certainly hit a lot and when it hit, it hit hard.
Parks And Rec had the longer-running story arcs and more than one will-they-or-won't-they stories that certainly drew us in (moreso my wife, but then I feed off her interest and get interested as well) much like The Office. I also felt that there were more endearing characters. Oh, and Ron Swanson.
Of the two, I'd probably give the edge to Parks and Rec as a whole, but man, did Community have a whole bunch of brilliance in its too-short run.