Identifying people in old photos

Hi all,

I have an old photo (about 1908) from a studio that no longer exists, not surprisingly.

I can identify about 2/3 of the people in the photo, thanks to my great aunt, who gave me the copy.   The people I know are my great-great grandparents, and my great grandparents and their various relations--siblings, cousins, children.

In the center of the photo are seated Johanna Weisinger Huber, my great-great grandmother, and her sister, Frances Weisinger Tromposch.  Both of their husbands are in the photo, as well as several, but not all, of their children.  The Weisinger sisters came to America from Vienna about ten years apart (with Frances and her husband, John, arriving first).  Johanna and Franz Huber came in 1908.

I would like to try to identify the people in the photo I don't know.   As all the people I do know are related to Frances, Johanna, or my great-grandmother, Adele Huber Tatick, I (and my great aunt) strongly suspect that the other people are relatives of the Tromposches.

I have made photocopies of the photo, and mailed it out to about three dozen Tromposches from the NY Metro area.  I have received some lovely, thoughtful letters and emails from people, but no one seems to be related to me or recognize any one in the photos as someone from their family tree.

What would your next step be in trying to identify the individuals in this photo?

BTW--Frances and John Tromposch had three children (my great-grandmother's first cousins).  I grew up knowing two of them, the third having passed away before I was born.  None of the Tromposch children had children of their own, so I am definitely looking at cluster relatives.