I launched on the Sabine river Tuesday from the city ramp and went north. The current was flowing pretty good on the main river so I decided to turn around and head towards the Blue Birds Fish Camp area. It was off color but there was less current. I only fished for an hour with no luck. I just wanted to get out and run my motor. I feel getting into backwater areas could produce a few with patience. The logging cuts north of IH 10 could be ok right now. The old hwy 90 area(burned bridge) may work also.
All the rivers you mention can be fished from a boat. The brazos and sabine are the two I know best and have done so by studying maps and reviewing websites. Now is the time of years to hit them for san dies. Get a boat and go.