Recently there have been some strange things happening where new users appear to have been created purely to flag the posts of others. Can the ability to flag posts for spam etc be restricted based on the rank of the person? This way it would be necessary to have at least spent some time and effort in the forum before being able to troll people!
I suspect that in response to the recent trolling some people have been retaliating by supporting their friends by systematically liking/agreeing/lolling as many of their posts as they can. This is a reasonable and expected response and difficult to put rules in place for. However, you could also restrict the ability to like/agree/lol a post based on rank, which would prevent anyone creating new users to promote themselves as well.