I don't think I have ever seen anyone use a flexible PCB in a keeb build yet. Do you know of any websites or services that will take an existing solid PCB design and turn it into a flexible design? But I definitely would like to. As for wire-wrapping, I definitely think that could have been done here. The build I posted was just the first proto-type AFAIK. So he probably didn't really feel the need to go all-out.