1: Utility is heterogeneous. Which gives you more "utility", a bowl of ice cream or a chair? The question itself is nonsensical, the quality/type of utility gained from a chair and a bowl of ice cream are entirely different.

It's not nonsensical; it means “would you rather have a bowl of ice cream or a chair?” Of course the answer is “it depends”, but no-one ever claimed that U(x + a bowl of ice cream) − U(x) doesn't depend on x.