I have not read books on diving on the "Doria;" however, I have watched some documentaries of exploration with mini-subs or equipment done on the "Doria." It was long thought that her safes contained all this money and all these valuables and, when they opened them, it turned out to be false.
I've read a book and some accounts on what happened between 11 pm on July 25, 1956 and 10 am on July 26, 1956 when she rolled over and gave her last gasp. Everyone blamed the Swedes because their ship rammed the "Doria." Realistically, both sides were at fault. The Swedes had an unseasoned officer driving the ship through heavy fog in a heavily trafficked maritime lane, the radar was set at a scale that was 3x bigger, or smaller, than the true distance, and there was possibly some alcohol involved. On the Italian side, there was a breach of maritime protocols in which way you are supposed to turn (left or right) when you confront an event like this and they panicked. (To think that a sharp turn in the other direction would have avoided the collision is something that must have haunted many people for years.)
As far as diving goes, she's on the shelf of the Atlantic before the edge of a big "canyon," so she sits in about 240 feet of water. Sharks are also a major problem in this area, as if we don't know that from the news. Some say that the "Doria" is considered the "Mt. Everest of dives."
She was not a big ship. It was more about what she meant to a nation which had typically had good rapport with the U.S. healing from the ravages of WW2 and embarking on a rebuilding campaign that went for some 20 years, which Italians call the "boom." And how that nation would transport its people moving to the U.S., and back, including American tourists crossing the Atlantic that way instead of via the not as prevalent long haul jet. That said, while not big, they lavished a good bit of attention on the cuisine, the creature comforts, and how she was decked out. For Italians, when it comes to their transatlantics, it's the "Andrea Doria" and the "Michelangelo" - their very last and quite a bit bigger flagship (1965-1977, in my background photo; to 1991 under another country's flag) - that they more vividly remember.
* I'm off my soapbox now *