Different strokes, but I would skip the Katy and just stay with the TA or a road alternate. I have generally found that whenever we used a bike trail on tour, especially unpaved ones, I almost always wished I had just stayed on the road. The exception being the nice trail system between Frisco CO and Breckenridge CO. We took a slightly more direct route that crossed over the Mississippi on a bridge rather than the ferry. I don't recall the route off the top of my head, but we found it pleasant.