thanks for the feedback and request.The S in the new ones formed by line and circles can represent yin/yan, as you stated or also two countries separated by water or two countries connected by non-directional path. #88 can since it is within the circle (circle of course can represent grouping, or continuity, or further the yin/yan concept or the world.....
Pls let me know if you have any other requests (including ones for fonts, colors, additions, subtractions or....). Happy to try the variations for you.
C