I agree with you that most of the time spent is on the hood, trunck and maybe the roof by some. In any case coming down to your plan.
I completely agree with it. The trick is to always start with the LEAST AGGRESSIVE approach and the reason why I say approach is so that I can refer to both the pad and the compound.
Answering with respect to your specific answers.
So here lies one of the points that I think you have identified yourself. Keep that light pressure applied all the way through, it shouldnt be too much especially on a polishing pad so try doing that. The mild increase in pressure would help you generate that minimum cut that you are looking for.
You can always increase the number of passes from 4 to 6 or even 8 on each section especially when you are just putting in light pressure and a very very mild abrasive compound. With the PCXP you dont even have the chance of the pad heating up like you would have in a Flex.
so shorten up your area.. Im assuming you are using a DA for the first time right ? A 2 x 2 is usually ideal for starting and getting the optimal results you need because neither the product dries up and you get good OVERLAPPING passes.
That is good always do sections. In a hood divide it into 4 by a horizontal and a vertical line and maybe test 2 different combos and on it and see with which you achieve the best result with the mildest possible approach.
Hopefully you wouldnt need to come on the orange pad which has a fair amount of cut as well.
One more thing that I wanted you to know from the chart is that this describes the Softbuff pads and not the more recent Softbuff 2.0 pads which I think you have, which have a slightly less cut than the Softbuff only. Thats why I said that your pad would match very closely with the Orange one and is not high up. So moving to that pad wouldnt make a huge difference. 
I love the fact that you pick up on things very fast.. Keep it up !
