Ow did Silla develop after Unified Silla?(Korean history)

Hi, I just want to wirte about how Unified Silla develop with Family Clan, Buddhism, and Hwarang. I wrote some my essay…I hope you understand what I want to really wirte about…
If you dont get clear about Family clan, you can remove..but about Buddhism and Hwarang should be in! Thanks

When Koguryo and Peakche became waker, Silla politically didnt have much power unlike two kingdoms had power at that time, Silla eventually needed to help them to win the war against Koguryo and Paeche. Silla made a Silla-Tang allied army across the sea, so Silla successfully conquered the other two kingdoms.

Truthfully, the purpose of the Chinese was planning to conquer entire Koran Peninsula under Tang imperial control, but Silla couldnt also accept them to conquer entire peninsula to Tang-china. Therefore, Silla conserved the independence of the Korean peninsula, so Silla finally made one of the longest sustained a dynasty in the history of Korea.

In contrast to Koguryo and Peakche, Silla took special reasons to accomplish unified Silla. Silla had to control all over the territory and population to stabilize economy and politic, so they required a prominent authoritarianism by throne to rotate among the three strongest clans, by Kim, Pak, and Seok. The significance of power of the clans increases a full political and societal development for the Silla unification unlike Koguryo and Paekche.

Moreover, Buddhism had adopted by King Sosurim in Koguryo period, but King Bophung officially had prevailed Buddhism in unified Silla. His work was involved in the development of the Korean Buddhist thought to support by all people.

After King Bophung also established the Hwarang, King Munmu flourished the Hwarang to compromise between the king and the aristocracy. King Chinhung also broke out prejudice that the Hwarang is only organized to hierarchy.