Sorry, very very busy right now, but after a *very* quick read:
It needs a real form. Where are you writing, what is it featured in? A magazine? A forward to a book? It can't just be an essay.
Length: It's OK, but you probably know that they have to be a lot longer for Yr 12

Very good for Year 10
A lot of "reality.... reality..... reality..." this is the biggest trap. Don't mention reality too much. Break it down. Focus on one section of the context and be specific to it. For my exam, I wrote a reflective piece by Michael Frayn (the authoer of my chosen text), and focussed on how he had tried to mould a representation of reality through his writing. I went on to explore how one character's perception of reality could be modulated by the forces of time and the suggestibility, the fallibility, even, of one's memory.
Also crucial is the exploration of both sides. OK, human's definitely veiw the outside would through an irremovably subjective lense. Does this, however, mean that we do not inhabit a world defined by objective limitations and principles? A chair is a chair. The extistence of a stone cannot be denied by merely classifying its label as a "stone" as subjectively derived. Think about these ideas. This will help you give your piece more balance and complexity. You can still have a final viewpoint, but you should explore the opposing view and even rebut it to some extent.
Hope that helps!