Thalassemia intermedia does cover a wide area, and as you've learned from the counselor, your husband's gene mutation is one that often results in intermedia when combined with another thal gene. Because there are other factors that modify how each gene works, and also possible factors that effect how much fetal hemoglobin can be produced in an individual, it is difficult to predict the ultimate outcome based on the gene mutations alone. Intermedias often do not transfuse or start at a later age than majors. Their blood demand is usually less frequent than with majors, when they do need to transfuse on a regular basis. Transfusing intermedias also need iron chelation to remove excess iron, but even non-transfusing intermedias can need some chelation, as the gut will absorb too much iron when the Hb level is chronically low, as seen in intermedia. Quality of life depends greatly on the treatment program, but thals live fairly good lives these days, complete with careers and families, as long as a good treatment program is in place and the patient complies with the program. In the US, the best treatment can be found at the Centers of Excellence.
IVF does remain a solution for many couples who find that both carry the thal gene. This can guarantee that a child would not even be a carrier.