It's clear from the various posts that you have many options when adding a roof over these walls.
The last poster's suggestion is to ignore the masonry walls and make an orthogonal roof over them with parallel eaves and ridges, but with varying soffit dimensions.
If this is acceptable to you then you might have as a simple roof structure and finish as you could.
Otherwise if you must have parallel eaves and ridges you must either accept a roof surface that is not in one simple plane, with twisted facets are needed to achieve the form, or a piece of 'flat' roof at the ridge to fill in the inevitable gap between the two single-plane roofs that meet there.
In these cases you need to consider the complexity of making the non-conventional roof structure and its finishes.
If parallel eaves and ridges are not a must, but single plane roof for each section are still preferable, then you need to decide it you are to slope the various ridges or the various eaves. The former is probably the more conventional structurally - it's effectively a very shallow hip construction with the normally horizontal ridge-board becoming in effect a sloping hip-tree - the roofing material is easily trimmed and covered by the ridge capping: otherwise sloping the eaves means non-conventional sloping wall-plates, odd-walling etc, and probably ugly weirdness at the lower edges of the roof, where material at the eaves would need cutting and finishing oddly - somewhat like a shallow valley gutter...