Political system to automatically vote system for optimal life for everyone

What would a political system where you could cast a percentage to each party and have that percentage count as the amount of influence you would want that party to have in politics according to how safe your life would be if it were to win.

And, would such a system be fair. Cause one person may cast some percentages, another one others, and a robot could easily determine the optimal percentages for each person, that that person could automatically use as their vote.

But, then, if these percentages represented safety, how works you combine them to yield the perfect vote (of the system, to government). Thanks.