I disagree anyone has the capacity to use it properly or abuse it, irregardless of rank. That's why I like the idea of needing to be whitelisted. The requirement might be your account needs to have enough substance a Mod can make a determination on whether you need it or not; or if it's a net benefit to allow someone to use it.
Sound is like moderate thread by forum moderator. Who will be responsible if in case happen any scams from self moderated thread? if its whitelisted by forum moderators? Usually forum user will raise question why moderators approved this self moderated threads? But id its auto whitelisted based on rank then I don't think there will remain any space to raise question if anyone get scam. Because that time it will be a normal procedure.