I personally find that adding a diver, or divers, to a image creates a lot of artistic opportunity. As you probably know, a diver can act as the subject, or as a secondary subject, and can serve to draw the veiwer into the image to make some sort of connection. People are often attracted to an image of, or with, people as it provides a common frame of reference for the scene.
Having said that, working with models underwater takes a considerable amount of patience, dedication and appreciation for the fact that your model has gone to a lot of effort to even just be in the water and that their contribution to the image is valued in some way. I work with two models at the moment and while the process and results have been rewarding (to me at least), we are constantly working together - in terms of positioning, trim, buoyancy, awareness and hand signals in order to achieve the artistic goal of the image. It's not easy, but I feel it is well worth the effort.
If I may, here's an image I made on the weekend wreck diving with my two regular models. With no prior discussion of the idea, I saw an opportunity, signalled to them and this is what they helped me make.

As for your image, I like the idea, but unfortunately I find the yellow octo hose and reef stick thing very distracting. I also think the image could be greatly improved by simply having the diver's eyes up and over away from the sponge like they are trying to hear or listen - rather than looking at the camera.
Hope that helps.
Lee