I dunno, I love to analyze stuff to death, but this might be one of those "just do it" ideas. Maybe it's the irregularities of homemade pinholes, but my experience is that there is relatively minor variation with a fairly broad deviation from optimum with a pinhole. You might just try a few shots with a middle of the road sized hole and see what it looks like. I would think the location of the filters wouldn't be that important either since each piece of film ultimately only sees the cut off spectrum. This would seem to be an interesting project -- let us know what happens!