You could keep a crowned belly such as a English longbow
If it was weak in tension, whatever that means (stiffness? flexibility?) I don't think it is..
ie I think such a cross section would be good for yew, juniper, incense cedar.. but not for oak, maple, hickory?
I think it makes more sense to have a crowned back with red oak, but I think I will just trapezoid it with a rather slight rounding, not round it
Apparently the old Tudor English Warbows actually had an oval cross section..