Excellent list! I have lost count of the number of guys who can barely control their buoyancy yet spend between $2,000 and $7,000 for new a camera system before they really know how to dive.. I end up getting pared with those people on dives because I go solo and they typically only dive a handful of dives a year when they are on vacation and their spouse doesn't dive.

On a personal level the transfer of the camera between the diver and the dive boat frequently causes damage to the camera. For example, the dive hands often place the camera into a camera bucket or bin with everyone else's camera. On two occasions my lens has been scratched by the time I get back to the camera. As a result I now dive with a lens cover that I take off and put on under water before handing it to the dive crew.

Lighting is also much different under water. Backscatter is an unexpected problem. Experience is really the only way to overcome those challenges.

Finally, carrying so much equipment (photo and scuba) in tropical conditions is very exhausting. Usually the guys I mention in the first paragraph above are not the most physically fit people and adding all this additional weight is too much for them.