How to have prevented the collapse of the Han Dynasty?

The Han Dynasty was one of the most influential Dynasties in China. Under its rule, the Chinese culture was able to expand to Korea, Vietnam, and Central Asia. Although, with great expansions came great economic and political troubles that I feel the rulers of the Han were just not ready for. To begin with, I believe the Han Dynasty did not necessarily have to collapse. Intact I am about to share, what I would have done to save the Han Dynasty from falling to its doom.

There were several problems in the structure of the Han Dynasty to begin with. I am not going to say that the only way to save the Han Dynasty is to have it begin with a different governmental structure than it did because it is clearly unlikely that a ruler from around the first century BCE would listen to a governmental offer that establishes equality between the ruler and his subjects. In this case I would also not say that to prevent the Han Dynasty from falling, a more wise and less greedy person must have stepped in. Instead I shall explain where I believe things could have been turned around for the better in the Han Dynasty's fall. If you look back closely, each ruler that succeeded the last made attempts to rectify the last rulers mistakes. For example, when Liu Bang had given too much land and power to family members, and found them to be nowhere at the time of need, other the rulers that succeeded him decided not to give family members lots of land and instead give it to officials that can regulate minor districts of citizens. Then came along Han Wudi, who emphasized the importance of education that previous rulers failed to acknowledge as useful, but he too soon fell because of investing too much in the attempts to prevent the Xiongnu's rule. The were a strong nomadic group that was able to spread their influence in a good part of Asia but were stopped my the Hans Military under Wudi's rule. Along with stopping this threat, Wudi also expanded his empire to most of central Asia, Korea, and Vietnam. Though this secured the safety of the empire it brought several problems involving stability. Too much money was spent in stopping the Xiongnus and expanding the empire, therefore leaving economic unbalance where the rich were growing too powerful and the poor were growing too week. Poor people were engraved in debt and had to sell of their land to the rich or sell themselves as slaves, who also served the rich. With such instability, rebellions and banditry made sure the Dynasty fell. So how could this have been prevented? When the ruler Wang Mang came into power he had attempted to establish as system where there was a limit to the amount of land a person could hold, but this idea filed due to poor delivery of an explanation to the people on how this would work. Therefore the rich neglected to give up their land and the poor did not gain anything; rebellions and banditry continued. I believe that if Mang had built more upon his idea and assured that there were certain limits to property ownership there wouldn't have been such a huge instability in the Hans society, since it was an agricultural based society. Meaning that if land was accessible to most people, they could harvest and form a stable structure for a working economy.