While I agree in principal to your SS proposal, that would be one worthless voucher. There’s nothing in the SS “Trust” Fund but an accounting entry for you and I and everyone else. Congress stole that money decades ago.
When it is cashed in, they will print money to redeem it. That will lead to inflation, but still, it is the best idea I have heard of. So long at the rotten payroll tax stops, and the rotten promises don’t continue to be made.