Kennywood, well frankly the earlier you get in the gate the better. Double this if it's a weekend, your safer with Tues-Thursdays since the biggest crowds are Fri-Monday. Also the earlier you get there the faster you can hit Skyrocket, which always has the longest line in the park being newest. The other biggest lines are often: Exterminator, Aero 360, Ghostwood Manor and Raging Rapids. As of a week and a half ago, schools where still having picnics but the crowds where decent. We only waited about 25 minutes for Phantom and less for the other coasters, minus Skyrocket which naturally had a 2 hour line.
...also don't forget the Potato Patch Fries! It's a tradition!
What Day will you be at Great Adventure? I'll be there this Sunday and next Wednesday. If you're there on a weekday you may not need the FlashPass, depending on the school/camp bus traffic. Pretty unpredictable. You're coming from quite a distance, so FP may be worth getting if you only have one day at the park. The crowd pattern has changed slightly with the opening of the "NEW" Green Lantern. GL, Superman:Ultimate Flight, and Kingda Ka are all to the left and within shouting distance of each other. The lines build quickly and remain constant. I often end up skipping KK and Supes if the wait is more thn 30 minutes. El Toro's and Nitro's lines will be longer in the afternoon. Bizarro hasn't seen bad crowds on my three visits this year. Dark Knight is one of my least favorite rides, but the air-conditioned pre-show is the best thing about it. Crowds have dwindled there too. Have a great time..you're visiting three parks I love to death!
Walt Disney World's Magic Kingdom
Disney's Animal Kingdom
Disney's Hollywood Studios
Disney California Adventure
Universal's Islands of Adventure
Universal Studios Florida
Universal Studios Hollywood