Outbound has come up with a "Wedge" design, a 5 X 10 with the back end tapered in a wedge shape. I am not sure what I think of it. It is cute, and shouldn't drag bottom on the rear end.
https://www.outboundtrailer.com/models I can kind of see the purpose, maybe, but still, I am not sure the loss of not having the extra space that a 5 x 10 would give might not be worth the times one needed the higher end.