[eluser]Tominator[/eluser]
I've got question: Where is the problem?
In my sites I am using special column (in database) to set what level is the user. Maybe it's not the best solution, but it works great. When user register, script set his Level to 1. You as admin can set value of his rank to '3', and then user will be moderator. If you set '7', user will be VIP (or gold member). When you set value to '10', user will be admin (as you). I think it's easy and smart
(Yes, I'm really not very well in English, but I'm trying to help you
)