Something I did when I made the Junker Marauders, was I applied the 5 Ws. Also known as a the kipling questions:
Who
What
When
Where
Why
Sometimes How is also applied.
InRP: 5 Ws:
Who are you?
What does your faction do?
When was your faction established?
Where is your faction based?
Why does your faction exist?
Then apply it in an ooRP context:
Who are you? Will people take you seriously?
What do you want your faction to be? What does it offer that's different to other factions? When Where
Why did you decide to make this faction? As a leader, what are your goals?