We'll be at Marla Dorrel from now on for Tuesday's playgroup. It's big and shady with plenty of different play structures, and it's fenced most of the way around. It's also right next to highway 64, which makes it accessible to most members of the group.
There is a greenway that leads to the pedestrian bridge over 64. It's a 10 minute walk, so bring a stroller because everyone once in a while we'll head down there to look at the traffic.