Mars conjunct Neptune can be included in the positive quotation as well as the negative.
Good point, and this is the case always with anything. I like to think of it in two ways; firstly, fitting all the pieces of the jigsaw together, and then looking at the complete picture; and secondly, this shows the interplay between astrology and free-will.
It is important to look at where the planets are posited in the chart, as that shows the area(s) of life where they would be likely to play themselves out. So two people having the same aspect involving the same planets, and so carrying the same energy, would live the aspects out in (either of, or both) the areas where the planets are placed. In the case of NS, I have briefly touched on this in my previous post.