Allerton is GORGEOUS, how could it ever get a less than perfect review. I've been going here since I was little, and it's a central Illinois institution. It's a unique and stunning place that you can go to for so many reasons. Some of the reasons I've used it for or been including in are weddings, picnics by the pond (or anywhere), kite flying/frisbee throwing, general walking around, play day for your dogs and/or kids, photography, etc.
Fact: once I was sitting by the pond, looked over, and a legit full grown bat was hanging from a tree near me. Just chilling.