An Old Hwy 20 bike route would be a wonderful thing. Unlike the Hill Country further to the west, the terrain between Houston and Austin is flat enough to be managed by many recreational cyclists.

I could see bed & breakfast operations catering to cyclists popping up along an Old Hwy 20 route. I read somewhere (sorry, no citation) that around 15% of the tourism income in towns along the Longleaf Trace in Mississippi comes from bike tourism.

Elgin, Brenham and Giddings are interesting places for short visits. There also may be smaller near-ghost towns along the route of historical interest. The existing roads between Houston and Austin are not very bikeable and most of them take you out of the way you would want to go.

However I couldn't find anything about the project on the GEDC website.