dmjlambert:
Are you overthinking it? Design your board according the requirements the PCB manufacturer such as minimum trace sizes and spacing, have the boards made, and show off to your client the certifications that the PCB manufacturer says they have. For example, if you get the boards made by pcbway.com it has ISO 9001 RoHs UL certification PCBWay get IATF16949, ISO 9001, ISO 13485, ISO 14001, ISO 16949, ISO 45001, CE, UL, RoHS, CQC and REACH Certificates - News - PCBway
Your suggestion is indeed so nice...