> a board, requiring 2/3rds majority in a vote
So instead of merely depending on the feelings of the accuser, it depends on the feelings of two thirds of the board? That's not much better. You can make objective rules that are not subject to feelings, you just have to be willing to not please everyone. When you don't have objective rules, people are less likely to participate in the game because people can't be sure that they aren't breaking a rule.
The board has a set of rules, that is the CoC. However as in any case where people are involved, they will have to deliberate and discuss to reach a conclusion.
Perfectly normal.
If you have a set of strict objective rules, some people will find a way to game them, and still harass people.
And harassment/belittelment is always a question of feelings. You can't set up a clear concise objective standard. It's a case by case thing.