>You’re also subjectively adding that “maintaining well being” is a positive in your example.

That's not what subjective means. Expanding territory is in this case meant as always being a positive, which doesn't have to be so. Well being is clearly defined, your body dying is not maintaining well being. Hence always objectively good and bad by the condition provided. I think you've missed the part of philosophical teachings regarding good and bad that states regarding health issues and a few other things it can very well be made to be objective.

>I already showed that everyone suffers by definition. That is true regardless of whether or not they view their lives as a net positive, a net negative, or neutral.

You have not. You implied all people suffer by definition, but that is not the case. People suffer when they have more hardship to deal with than pleasure they feel. You're looking at it from a very nihilistic and negative view, that any bit of hardship means people suffer. If we follow your reasoning, I can also argue all people are joyous. For they have moments in their life that are joyful, tasting food for example.