Nice paper. I enjoy reading it.
Though they divide the universe differently, and draw different boundaries, these concepts or theories have in common that they do all divide the universe somehow and do all draw a boundary somewhere. Each listed theory conceptualizes the self as something compound or having parts and a structure, something changeable, something with a boundary which in some cases may expand or contract.
I agree.
I can’t be really sure whether Henology may have a good role here. As I understood the first part of the paper, Mait Edey did a critic on subject-object relationship because some philosophers had drawn different boundaries, splitting everything radically in different parts.
If I am not mistaken, Mait Edey wanted to explore a solution where reduction of the variety of existences back to a single stuff or substance. Thus, Henology.
Without consciousness, none would be “self”.So let us focus the meaning of “self” here in what is literally a radical manner — getting at the root. Consider the terms of such familiar distinctions as between, for instance, observer and observed, seer and seen, hearer and heard, or thinker and thought, where the role of consciousness is explicit.
There cannot be an object without an observer/subject/hearer/thinker, etc.
So as a practical matter, for the sake of argument, let’s accept Gallagher’s stipulation and focus it by saying that “consciousness” and “awareness” are equivalent where their meanings overlap (while acknowledging that in common usage areas may not
overlap). Of course, we each may size and locate the areas of reference somewhat differently. But if we can agree that there is indeed some overlap, albeit so crudely conceptualized, then we ’re in a position to notice that the overlap is the really interesting and problematic part.
Indeed, that was problematic and complex to follow. 
It appears to you, not you to it.
I think this is very open to debate.
It is true that planets (for example) do exist even if humans would have never been born to look at them. However, thanks to our observation and contemplation, we gave a “presence” to the planets in the universe.
With the observer (us), the planets have a meaning in our reality. Without the observer, the planets were merely chunks of spheres gravitating in space. So, I honestly believe that we appeared to the planets, and not vice versa.
Overall, a nice and interesting paper.
Disclaimer: I’m a rookie in philosophy, so take my opinions on this paper with caution. Thanks!