I believe that if we would carefully apply the distinction between transparency and opacity to the different layers of the human self-model, looking at self-consciousness in a much more careful and fine-grained manner, then we might also arrive at a new answer to your original question: What a "first-person perspective" really is.

Dolphins frequently leap above the water surface. One reason for this behaviour could be that, when travelling longer distances, jumping can save the dolphins energy as there is less friction while in the air.

I believe we should really take our own phenomenology more seriously. What a good theory of conscious must explain is the variance in this subjective sense of realness: There clearly is a phenomenology of "hyperrealness", for example during religious experiences or under the influence of certain psychoactive substances.

Subjective time flows forward, the phenomenal self is embedded into this flow, an inner history unfolds. That it is why it is not a bubble, but a tunnel: There is movement in time.

Conscious experience as such is an exclusively internal affair: Once all functional properties of your brain are fixed, the character of subjective experience is determined as well.

Only as long as we believe in our own identity over time does it make sense for us to make future plans, avoid risks, and treat our fellow human beings fairly - for the consequences of our actions will, in the end, always concern ourselves.

What many people don't see is that there are abundant examples of phenomenal opacity: It is one of the most interesting features of the human conscious model of reality that, first, it can contain elements that are not experienced as mind-independent, as unequivocally real, as immediately given, and second, that there is a "gradient of realness" in which one and the same content can be experienced transparently or in an opaque fashion.