Hi,
I was looking at a large part I've designed and I realized that while most of it would be fine with 2 perimeters and 20% infill, there are a couple of places where I'd really like 3 perimeters and 50% infill. Do any of the slicers provide a way of doing this? I could imagine either dragging out regions on the 3d view to define a volume that needed different slicing parameters, or maybe modelling it as two or more parts that would be sliced together but with different parameters. The latter would be like is done for multiple extruders, but my quick look at that area suggests the only change between the parts is the filament settings, and not the structural parameters.