What was left unsettled or unaddressed in the Constitution after the Articles of Confederation were abolished?
They're were major changes introduced in the constitution and compromises made. What topics or concerns were not really addressed...?
A number of topics were sort of left unaddressed, or at least poorly addressed. Perhaps the most fundamental of these was the issue of the interpretation of the Constitution. The Constitution itself does not say who has the last word on what the document means. Today, we take for granted that the Supreme Court has this power, but there is nothing in the Constitution that says that the Court can strike down laws passed by Congress if they are unconstitutional.
An issue that we now see as quite important that was not addressed in any real way was the issue of women's rights. The Constitution did not say anything about the status of women in their society. It does not say if they are equal to men or unequal. It just leaves the issue of the status of women completely unaddressed.