Some very useful tools, especially for offroad use, but also useful on the pavement are: 1. A small compressor or inflator; and 2. A tire repair kit including a rasping device, repair patches, seating tool, and cement.
Fortunately I haven’t needed the tire repair kit yet. The compressor is useful to reinflate low or leaky tires. The compressor also allows you do deflate your tires so as to increase the bearing surface and improve traction especially when driving on very loose sand. After negotiating that area, you can easily reinflate for highway travel. These compressors are cheap (~$30) and smaller than a loaf of bread. And don't forget the tire gauge.
Boards such as thin plywood can provide a firm surface from which you can get traction if you have become stuck on very loose ground. That could occur not only in offroad travel, but also when simply pulling off the road.
A tow strap is also a good idea.
John