And, i prefer Merit rather Up and Down. In fact, Merit can be abused by Higher Rank. So, with easier system like that. I am sure more abuse will happen.
~It's not a bad system, but people tend to give negative points even to good posts just because they disagree with poster. On the other hand, because points are renewed every day, there is no erason to hold them.
So that is example how the system abused.