I really don't see any advantages for having custom tags. More often than not, I felt it had a way more distracting and detrimental effect upon the discussion board at large.
Getting rid of the junior tag has a huge first step, a move which I feel should also carry over to custom tags as well. Only staff/mods, industry folks and representatives, and folk that have made extraordinary contributions (people like Mama Robotnik, and Durante before he officially contributed to gaming press etc.) should be given tags.