I love the idea of a 'thumbs down' button ... though I'm not sure exactly for what offense I would push said button. It would depend on the consequences attached. If it were that easy to lodge formal complaints, then I'd guess there would be hundreds lodged each and every day, with no resolution possible to any but a few of them. But I could be way wrong on that, though I don't think so.
Still, part of me would love to staple a scarlet A (for abuser) on the handle of anyone I thought had crossed my imaginary tolerance line and watch the color of that person's abuse icon change steadily from green to red as this joker accumulated similar button pushes from others who though he/she was abusive. Of course, there would be those that would distort that system as well.
Actually, from my point of view, the current system works well: all my lodged complaints have been dealt with satisfactorily in a timely manner. I haven't a clue about whether the system is swamped or whether it works for others, however.
Ah. Yes, that would make it far easier -- and perhaps even pre-empt a few of these threads.