I don't know anything about the tiers on this place. When I rp I don't rate the strength or power of my characters and give them a tier number. I put into perspective the number of people inside the story and the level of the fight that I want to write about.
So I normally do it like this: Realistic story line battles would be my tier one
Fantasy would be my tier two
and so on so forth. Based off of the strengths, weaknesses and powers involved in the story. With each higher tier is a more power based story. I have no idea how they do it here I didn't read up on it. But that is why I don't give tier my characters or stories. I find it pointless. To me all that matters is that I role play either high casual or advanced. If you can't keep up I won't bring myself down to your level, I will however bring my character down to your level.
I doubt that made any sense at all but that's how I do it.