Im doing a 3 day 2 night ride on the Katy trail in 5 weeks. Should be a blast.
The trail is about as well set up for an easy trip as you can hope for. There are hotels and b&bs all along the trail, and camping spots are all along the trail too.

Ride east from Sedalia, camp a couple nights, and then hop on the train once finished to get back to Sedalia.