If leaders wanted to created a govermment that is more effective than the governmment under the articles of confederation, which is the most important idea that should be embraced?

I believe that the best answer to the question: If leaders wanted to create a government that is more effective than the government under the Articles of Confederation, which is the most important idea that should be embraced? would be: a national government that shared equal power with the state governments. One that were much stronger than it was when it was first established, to become the balance. In this way neither each individual state would have the upper hand on the other, nor would the states have more power than the national government.  

Explanation:

When the national government in the U.S was established by the Articles of Confederation, this government did not hold any power whatsoever, with the state governments leading everything. However, this soon became a problem as there was no balance between the different states, and also, there was no central government that could mediate in matters that affected the nation at large, but that each state would have pushed to make it so that it favored them, and not the others. Finally, they realized that there were issues with the topic of taxation, and also defense against possible outside hostilities against the nation. Although a national government was established, it was much later that its powers were increased by the new Constitution, so that these needs were met.

disease was the number one killer of native peoples. they had had little exposure to the diseases of europe. this led to some villages being almost completely wiped out and some tribes destroyed.