I think the roof pitch is more or less fixed; the perimeter/overhang and the peak location fully define it, apart from the ridge beam width I suppose (I prefer it to be slightly narrower than the wall faces since the taper is more visually appealing, not sure if that will be noticeable in person, though)

HAP; height above plate. That's a great term that describes my question perfectly; the height of the plate and rafter gap is not consistent wall to wall. On the diagonal walls (NE, NW, SE, SW) it will actually slope at some shallow angle.

When you say the plates can be different depths, are you referring to how deeply the rafters seat down into the plate recesses? I think that could work, and would be much easier to lay out & accomplish before assembly. My only concern would be the 'tall' rafters either won't have as much support, or the 'low' rafters will be beefier than needed. The HAP is 6" higher than the N/S walls at the diagonals, and 3" higher at the E/W walls.

On last idea that occurred to me; though the hip rafters do not cross the corners, they do nearly cross vertical post members (close enough to be adjusted to match them). The Jack rafters could also be placed to align with the vertical posts (2ft centers). Would running the posts up past the common plate elevation to carry the taller rafters directly be advantageous? I plan on using purlins to support metal roofing, so the rafter/post connection wouldn't be an unsupported 'L' sticking up past the last horizontal support. I'd wanted to make all the wall truss elements identical for logisitics reasons, but maybe varying this one feature at the end of otherwise-identical posts isn't so bad?

I'll start up a proper design thread to get all these features in one place for discussion, since I now have a floor plan and rough truss layout.

TCB