Yes, there are masts and boats. What is missing is a centre of interest to catch and keep the viewer's attention.
Repeating patterns is a good compositional tool, but it's not working all that strongly in this shot.
Ike - you obviously had some thoughts when you put this image together. That is not the issue. The issue is how others that look at it react to what you have put in front of them and whether or not your vision is working for them. Will they stop and look at it or will they move on to the next image?
The triangle at the bottom formed by the water, the rectangle of blue sky and the repeating patters of the boats (the diagonal you mention) are all there. The question that you have to ask yourself is whether all these visual cues result in an image that someone (other than you) is likely to engage with.
In most images, there has to be a feature that catches the viewer's eye and that needs to be located in a visually appropriate location. The issue with diagonals is that they can work well in leading the viewer's eyes to a place where they engage with the image. If no such place exists, the eyes will often run off the page at which point the viewer has lost interest and moves elsewhere. In my view, that happens with this shot.
Ike, maybe take a couple of shots from this same vantage point. One where you zoom in more on the boats and the diagonal angle. The second, crop out most of the water and boats where the majority of the frame is filled with the masts of the boats. Leave enough of the boats in to know what is people are looking at but the main focus is the masses of masts. Trying saying that 3 times fast.