pcb design checklist
Ask you PCB manufacturer - they will tell you their constraints, and it will become a part of your checklist. Ask your certifying body, if you're planning to certify your product. Also, different kinds of circuits and applications have different PCB requirements. For example checklists for power PCB, rf PCB, high speed digital etc. will be different. The checklists for the same circuit topology used in automotive, aerospace, medical and consumer will also be different. You have asked a tough question. Typically, the PCB checklist is in the head of the engineer, and it's usually very vague.