What tags should we add?

On our previous platform, FLRon asked if we could categorize posts. His example was:

...say the topic “Baptism” was created. Could users then post their own sub topic such as “Immersion Baptism” or “Is Baptism really necessary”? There could be a dozen or so Main Categories that maybe the users could have input on. I’m thinking of categories like Second Coming, Sanctification, Current Events, Church, Prophecy, etc. Mix it up so it doesn’t come across as a CoG only discussion board.

What categories (called "post flair") would you like to see?