Several years ago, I would have given Kennywood 5 stars.
Now, the place is in serious need of maintenance, cleaning, and painting. I get the quaint history of an old, traditional amusement park, but time to spend some of the profit to modernize. The line at the Potato Patch took 45 minutes-yes, it was crowded, but that's a long time, albeit for a big order of fries with cheese/cheez and bacon.
Great rides, and the crowds are usually manageable, especially if you work counter-clockwise when walking into the park. A lot of classic rides, from newer coasters (Phantom's Revenge) to old-style wooden ones, like the Racer, Jackrabbit, and Thunderbolt. The newest ride, Sky Rocket (a couple years old now) is a lot of fun, with the initial quick climb a jolt.
Always a highlight of any summer trip to Pittsburgh, I recommend it to anyone who likes to ride without having to wait all day (ahem...Six Flags parks).