[jepler]

I don't know that there could be a single "best" executable format. Here are some thoughts, as a person who knows some about Linux and little to nothing about Windows or Mac. As sibling states, formats have largely stagnated but in Linux there's continuous progress on debug information. Another interesting area for research would seem to be executable/object file formats for fast linking or for later patching/updating. Of course, projects like gold and mold (and maybe the clang linker, lld?) show that substantial performance improvements can be had without changing formats.