Local politics should be more important than national politics. I don't think it mattered all that much who the president was in 1890. As the returns on violence grew over the past century, so did the reach of the federal government.
I do think voting is important but I try to vote in a way that would theoretically decrease that importance. I'm much more concerned with which powers we delegate to the government than with who runs it. You're right about Bill Gates being more powerful than you and me combined, but that's not due to any genius on his part as much as him benefiting more from government distortion of free markets.
I don't view democracy as a primary value. For me it's a derivative of my God-given rights to life, liberty, and the pursuit of happiness. A king would be much more efficient at preserving my rights, but democracy is the best risk-adjusted method since a king could easily violate my rights.