To me, remembering to check if my nose was on my face or not would be enough to spark the awareness and thought that leads to realising I'm dreaming - likely regardless if my nose was there nor now> I suppose it could also be shaped by your expectation and if you were expecting your nose to be there it likely would

I think it's also important to remember in terms of the clarity of the dreams that you're not limited by the physical capabilities of your eyes. Things might seem clearer because, well they probably are I know for certain I can see things in greater detail and higher clarity than my waking eyes ever could!