I've done other cars with an orange pad/SSR1 (I use Dodo Juice's take on the DAS) with excellent results... perhaps I'm being too much of a perfectionist on such a difficult colour.
As for not working it long enough... initially I'll work the polish in very slowly on 1.5 (at least 2 passes), then move onto another slow pass on 2.5, then another 2 or 3 passes on slightly higher speeds. When I did my bootlid, I divided it into 5 equal sections and would estimate that I took at least 5 minutes on each. In any case, the bootlid now looks pretty damn good: It's just the rest of the car that needs attention now!
Oh, with reference to paint thickness, I had a respray 18months ago so that shouldn't be too much of an issue for me. You do raise a very good point though!