Many thanks for the reminder about the many photos held at the iMuseum, and for your descriptions for searching these.
I have looked at them before but not nearly as carefully as you have described. After your message I had a closer look and was reminded that several also included short biographies.
For example, under Record type: First World War Biographies, is a photo of one of my Corkill relatives:
"Epithet: Soldier in the Royal Army Medical Corps.
Biography: Sergeant John Allan Corkill was from Ramsey. He joined the Royal Army Medical Corps at the beginning of the First World War and was posted to the Middle East. He was mentioned in General Allenby's dispatch from Palestine, in January 1918. This was probably for good work during the Third Battle of Gaza the previous October. Allenby's advance in Palestine would eventually lead to the capture of Jerusalem from the Turks, and so in some ways the campaign was likened to a final crusade. (Image ref: PG/14459)."
[This was John Allen CORKILL b.1893 married Annie CORLETT. John Allan CORKILL aged 56, of Thie ny Claghyn, Ballafayle, Maughold, buried Maughold 2 April 1950.]