Arch is a no based on the wife and I both being acrophobic.
A-B brewery tour is a likely stop.
In Forest Park, we may check out the history museum. We do enough zoos with the kids, and my wife it not into art museums.
Wife also won't do baseball games unless it's the Sox. I can't even get her to go see the Sox AAA team play.
Will look into the Delmar Loop. That sounds interesting.
We are actually staying in St. Charles less than a mile from Ameristar, so we probably end up in their poker room at least once.