You mentioned fishing. DW & I always try to spend our anniversary at Roaring River State Park, MO on May 1 (floods pending). It is a very pleasant campground with a great lodge for dining, if you want, and decent trout fishing without boots.
No real tourist spots near other than in Golden, MO the Pioneer Museum which is unbelievable for being housed in a tin building. The exterior is very deceiving. It's more of a hidden gem than a tourist trap.
The park is generally pretty full in the summer months, especially on the weekends/holidays. Probably best to make reservations. We prefer loop 2.
Our 2351D Phoenix Cruiser, Jack, has turned us from campers into RVers and loving it!