What strata of the population existed in Russia at the beginning of the 16th century?

The social composition of the population of Russia (Muscovy) in the 16th century was as follows:

The highest nobility, princes, the Rurik family, as well as the Staritskys, for example.
Boyars. Boyars could be voivods, they took part in governing the country (boyar duma).
Nobles. Servicemen, local cavalry, privileged. They received an estate for the service.
A few officials, clerks, for example. They served as clerks, worked in orders.
Service people. Sagittarius (since 1550), gunners.
Cossacks. Cossacks lived on the outskirts of the country, on the Don, Volga, Yaik. They could serve and tsarist troops and fight with external opponents (Khan Kuchum, Crimean Khan), or they could rob some merchant or ambassador.
Clergy. From the patriarch (since 1589) to the village priests.
Peasants. Most of the population, about 90%, they could be serfs, state, monastery.
The urban population, the townspeople, the artisans in the main. In Moscow, they could work at the Liteiny Dvor.
Merchants. It was a separate class, the most famous merchants, for example, the Stroganovs, they mastered the Perm Territory.