Making this tool available to users who have been here a year or over wouldn't work very well either I don't think, we have newer members here who are under that year mark but are very active, I don't think activity should be purely based on forum posts, I do a lot of other things.
I do agree with your earlier comment about having not having it visible to users if the thread has received spam votes, because it will cause a domino effect.
I really think the best idea is to just let the mods have the power, although I would honestly prefer if 2 mods had to vote to delete a thread instead of just one.
I'm gonna give that bitch a freeroll, bitches love freerolls.