There is a guy who did a stretch this summer. If you search you can find it on the forums. I have paddled from champaign, il to the gulf taking some small rivers then the wabash, ohio, Mississippi, and atchafaylia. While I have not done any of the illinois river I do have some experience on industrial rivers. If you have any questions I would be happy to answer to the best of my limited knowledge. I have found that camping has not been a major issue. I just set up at dusk and was out of there at first light. I have camped in some pretty sketchy spots. Water is an issue. I would not filter the water on those rivers. I always carried a lot of water. Hours on the water translates into miles. I always stayed in the canoe for around 10-12 hours. You can get fifty a day if you hit it hard. Barges are not a real problem. The ones you have to look out for are the tug boats or jerks in john boats. Good luck I would love to see some pictures and hear how it goes.
Classic Freestanding Rack