I’m not sure your original question about voltage and current got clearly answered. The answer about going multiples higher for reliability was a good one. You can go as high as you want on voltage and Amperage ratings for diodes as long as you are at least 20% above the voltage and amperage it will see. I always went at least 50% above when I used to design circuits for a living. I have used 1000 volt, 3 amp diodes in 5 volt 1/10 amp circuits, just because the company I worked for already bought those cheap, due to high volume, for other products. Higher rated diodes are also more forgiving of things like static electricity zaps.
Dave