One big thing I overlooked last night... how steep of a pitch do you want on those roofs? If the difference in height is not significant and the pitch is steep enough then the roof lines will intersect, which will add complexity and cost.
For example, with a 4/12 pitch (I don't know if I'd go less than that in an area that gets alot of snow, but you have to take extra precautions to avoid problems) you get (36/2)*4/12=6' rise on top of 10' of wall and the peak of the low roof is at least 16' (I didn't figure in the thickness of the roof structure to keep the math easy). So you'll intercept the high roof since it only rises from, say, 12' to 15'. Ooops... the peak of the low roof is even higher, so I'd go a foot higher on the right-side structure to make the peaks line up nicely:
Or since you're into a more complex roof structure at this point, build the high walls all the way to 14' to get the clearance you want without a cathedral ceiling and get something like this:
Note that the lower roof has to extend all the way to the higher structure, underneath the upper roof. It's just like a roof line you'll see on a partial 2-story structure. Be very careful to get everything sealed up nice and tight, layered properly, or water will find a way in.
