Questions on use cases and frequently used queries

Hi everyone, I just have some questions on what queries you are using and what are you using them for. 

From the list of queries in the query packs, what are the ones you are using on a frequent basis?

What are you using the queries for and to do what?

Are you using them for IT operations, threat hunting, vulnerability management, etc.?

What are some queries that are missing from the packs and you would like more of?