If we want to have actual heroes doing the research that will lead to such prizes, why not give reasonable career path to scientists?
THIS. With $33M a year you can fund about 8000 postdocs (NIH payscale), or 3000 professors.
Or you could directly fund your own institute, with positions that are more stable than the dreaded post-doc, but less cushy than the unfireable tenured professorship. Like Louis Pasteur [wikipedia.org] did with his Nobel money, to the enduring benefit of mankind.
Either of these would probably do much more for actual science than piling up more money on folks who are likely to have their career behind them.