Well, we've stayed at the DLH and the PP, and I have to say that we love them both.
However, our best trip ever (in October) was when we were at the PP. Funny how everyone says the PP has a boring pool. We LOVED-LOVED-LOVED the pool deck at the Paradise Pier. It's the perfect size and set up for families with younger kids - very easy to keep an eye on your kids there while they're running around swimming and sliding. Also, if you have young kids that aren't the best swimmers yet or are afraid of the deeper water in a pool, the water slide at the PP is perfect because it empties riders into a shallow catch-trough. NO SWIMMING REQUIRED for your kids to have a great time! Right next to the slide is a large wading pool (about 1.5' deep). Our kids would spash around in there for awhile, then they'd run up the steps and go down the slide about 10 times, then they'd hop back into the wading pool and splash around some more. DH and I just sat in the lounge chairs around the wading pool, relaxing and drinking some nice beverages, watching the kids having the time of their lives. It was the best and we did it everyday of our trip. We would stay at the Paradise Pier again in a heatbeat.