Hopefully XLAB, Torhans, Profile Design, and others will come up with something
I do wonder how the bottle mounts are positioned on the seat tube. Are they always a set distance below the top tube no matter the frame size? Or are they always the same distance above the seat stays regardless the frame size? Or do the vary based on the frame size? If they are based off the seatstays, then I think one design could fit snuggly down low following the tire ala speedconcept draft box. If they are positioned off the top tube, if only one box is designed maybe on large sizes it would look like the Ordu and small sizes be close to the tire. When I look at that Ordu I see a box designed to work on the smallest frame, but mounted to a large frame. You see this on the speedconcept where on the small sizes the top of the box is above the top tube and large sizes the top of the box is below the top tube, but medium it lines up perfectly.