I've had some really good days fishing past the No Wake Zone, but that also depends on where the buoys are located. When the lake is low and they're located before echo, I've fished several pockets of 18-20 feet of water between the buoys and Ship Rock. When the lake is full and pushing 100%, I've had luck between Ship Rock and Jack's Cove. When I first started crappie fishing (and had no idea what I was doing), the hot spot to fish was around that island before Ship Rock. I never caught anything there, but I've seen several boats pull crappie up left and right.
TL:DR - When the lake is full, there are several good areas for crappie fishing beyond the No Wake Zone