I'll add that i also was not successful in making desirable (read: texture and deliciousness) yogurt using a traditional yogurt maker. It was only in trying the descending heat method, brought to my attention by a French food writer, that I have had consistent success. As mentioned upthread, the richness of the milk will contribute to the texture and mouth-feel. Adding dry milk to non-fat milk should/might mitigate this. I just use whole milk and am delighted with the results. As good as I've been served in Europe. At very little cost.
When I grow up, I will make a batch using local Saint Benoit all jersey milk. The whole milk, at around $6/qt, is cream colored. I can only imagine the yogurt it would make! Compared to store-bought organic, it would not be expensive. Perhaps soon...