My experience of Iran has a negative point too: (street) food! Yes, it is true that we ate deliciously at home. But many times, while travelling alone, we went to restaurants where food was no big deal. The choice was poor, except for the usual two or three types of kebab meats. Or maybe kebab is just what we could get due to our language difficulties.
We were also told that Iranians do not eat in restaurants often. They still cook at home a lot. This could explain why the quality of the restaurants is not excellent.