If you want you income to increase with inflation you can't spend the entire rate of return. So If you are using a 5% return you should really only spend 2%, if you go with the current inflation rate.
Sure but that too is to die with a million inflation adjusted, not to draw down. Are you saying retirees should need to be able to live only on ongoing gains?
If you have accurate records for several ancestors who died of natural causes then you can put a reasonable upper bound on your lifespan. Do you have anyone in the previous few generations who lived to near 100? Lifespans haven't increased much for people who make it to adulthood.