In age old villages you can watch weavers working on ornate rugs. In the south you can stop at oases with sweet artesian wells and cool, covered markets. The hospitality of the people makes you feel at home. In the end your impression of this region will depend upon what route you take. It is like the African story of five people describing an elephant, one described the tail, one described the foot, one described the trunk, one described the ears and one described the ridge of the its back.
People passing along the main highways on the coasts usually have a low opinion of the countries.
If you get on the back-roads or head to select parts of the interior you will probably think the place is pretty exciting and has some first rate cycle touring. There are thousands of miles of paved roads and traffic volumes are low, but few have paved shoulders. Do be prepared for hills, especially if you are going to explore the northern third of the country or search out some of the more interesting places in the south. It is not until you get beyond Gabes in the south that you really have to worry to much about having an off-road bike. Most of Tunisia is excellent for road tour bikes.