a system with more choices has more opportunities to find candidates that you agree with on multiple dimensions of policy, as well as hopefully finding more candidates that you can respect as human beings.
the post you're responding to is proposing a kind of non-geographically constrained proportionally allocated representational democracy. so, instead of voting for just one of the 2 candidates in your congressional district (which is likely gerrymandered anyway) you can vote for anyone in the country and that person's voting power in congress is proportional to their popular vote count. that's not dissimilar to a lot of corporate governance systems (voting shares of common stock widely distributed).