I don't know what the future holds for Sango in InuYasha's adventures, but it's quite noticeable that they wanted to introduce her as a tragic character. In her first mission with her brother, her entire family is murdered. It all seems very well balanced; in the Toukajin arc, InuYasha almost died, but being immortal and the protagonist, of course, he was going to make it through. I had even forgotten that there were consequences in the world of InuYasha, but there are, and they are painful.
My current questions are: did she really not die, or did she resurrect from her own hatred? What is the connection between the Exterminators and the Shikon Jewel? And how did the Shikon Jewel originate?