I cut, case, tool, oil, dye, finish. I use rather thick leather 10oz plus usually.
Dying a whole hide might be cost prohibitive. What happens if you dye it black and someone wants Pink.??
To avoid stretching some people tape the backs of their project pieces with packing tape. (I think contact self adhesive shelf paper, would work for large pieces) Or glue it to a hunk of light cardboard like cereal box.