If there was one change I could make to the English language, it would be to have two words for “we”; one meaning “us including you” and one meaning “us excluding you”. Think of all the confusion that would avoid. For starters, that persona non grata (some would say spare wheel) would quickly get the message when you say: “We (excluding you) are going to the pub now”.
Of significance too, but of lesser importance perhaps, would be singular and plural versions of “you”.
Of course, if you combine the two, you would have four variants of the phrases covering the different cases of “we” stated above.