> The two parties will drone on about how other candidates are "spoilers" who only benefit who you see as the worse choice. That's nonsense, your vote should go towards who you think represents your interests best.
You need to learn Civics. I could write in my own name since my opinions are closer to my opinions than the Green candidate. What would that accomplish?
If, one day, the US introduces proportional or preferred representation then the calculations will change. In Australia, for example, you can vote (1) Green, (2) Labor (say) and then if the Green candidate is eliminated your vote is counted for your second choice. But if the Green candidate gets enough support then you get your first choice.
Even then, Democracy is difficult. In proportional systems, small parties can have disproportionate influence.