actually qin and sui are the two most important dynasties in chinese history.
the birth of Qin empire changed the historical track of china from feudalism to imperial times. the unification of china, standardisation of unit, currency and language. feudal states became provinces/counties under centralized government.
Sui dyansty unified china which already been seperated into north/south china for hundreds of years. Sui dynasty invented imperial exams(科举
which limited the power of noblemen and further reinforced central government. sui dynasty also formulated new ministry system (三省六部
, whiich was followed by all the dynasties thereafter..
The qin and sui are both very creative dynasties in statecraft but collapse very rapidly cuz go too far in political reform. Han followed qin's political system and prospered. Tang and Song followed Sui's political system and had unprecedented achievements in civilization.
there is stereotype that sui and qin were very draconian and inhumanedynasties, but modern historians think otheriwise. our perception of them are due to the "春秋笔法" of ancient historians.
first Qin emperor only buried four hundred scholars. think about how many people did zhu yuanzhang and zhu di (朱棣
killed. 1000 persons were killed for 方孝孺 case alone.