Is Vishnu a primary name or a secondary name?

From Gaura lila Prabhu:

Thoughts came in my mind regarding following names of Krsna:

Visnu : One who enters into every atom

Dwarikadhisha : One who is king of Dwarika

Vrajaraja : One who is king of Vrindavana

Laxmipati : One who is master of mother Laxmi

Rukmininath : One who is master of mother Rukmini

 – Visnu is name which is in connection with material world.

– Dwarikadhisha is the name in Connection with Dwarika.

– Vrajaraja is the name in connection with Vrindavana.

 Q1. Visnu is considered as secondary name; this is clear to me. What about the other 4 names; in which category they belong?

Q2. Is there any other category apart from primary names & secondary names of Krsna?