Remark
Let's refine your topic just a little.
Most of the rotten characters (the Monk and the Friar) are characterized as greedy, self serving, apologetic (meaning they make excuses for why they do what they do), lusty (the miller), the Wife of Bath (although to be truthful, she's pretty complex and I think Chaucer kind of likes her), the Manciple, the Reeve, The Franklin, the plowman, the Man of Law, and the Physician.
I think your question could be to begin with, how does each of them use money. How does money corrupt them (if it does), how is money and wealth obtained. How is money used. Are their any substitutes for money -- like the Wife of Bath and her 5 husbands.
What does the Narrator think of money? There is an old saying, you know what really happened when you follow the money. The rise of the middle class was absolutely impossible without realizing how the middle class began to accumulate wealth. That was their first step.
Some were corrupt. Some were greedy. Some were lacking in virtue. Some had too much and had few faults except in the way they handled money.
The Friar and Monk can be included in this discussion, because they cheated the church that they were supposed to be supporting. The Friar begged, but he had no use for those who had no choice but to beg, like lepers. Once you see how the middle class acquired wealth, you will see how they began to rise up the ladder of social control.
He who can tie and untie the purse strings, is he who can demand that others do his bidding.
