Great quiz. You could add book publishing - left is verso and right is recto. I am not confident that liberal means left in politics. Liberal is more in the middle. Conservative, which means in favour of gradual change, is the opposite of radical. Perhaps the meaning has broadened in the US.
Agreed. I typed in socialist and when it didn't work, I gave up on the category. Liberal is centrist; liberal-conservative (a term in use outside the US) is right of center. I would go with socialist vs fascist. Want to confuse kids - tell them to go counterclockwise or clockwise.
Conservative and liberal are mainly for US politics, it varies for other countries. For example in France "liberal" (economically) = right-wing, while the left is "social".
Liberal is central, not left