You level up every 50 posts. You become veteran when you reach 300 positive ratings, at which you can change your "title" like how mine says Rotten Tops instead of Level 10: Something Member.
Take a look at my profile
As you can see Rank does not matter. It is just some variables in the code and it matters not.
On a more serious note,
write a lot. useful ones.
To become a veteran, post good and hype-stimulating screenshots on WIP thread. It is a great and relatively easier way to earn positive ratings. I am sure 90% of my positive ratings came from that.
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