One simple solution to handling abuse is:

1. Allow reports of "abuse" be submitted by the community. (ie., flagging)
2. The incident of abuse can then be reviewed by randomly selected community members. These random participants will effectively act as jurors.
3. The jury can assign a score of abuse from 1-5 and depending on their average score punishment can be applied.
4. Punishment can be a variety of things, but downvotes makes a load of sense to me.

Minds.com does something like this and it makes sense to me, since its community based and no one person has a centrality of power.