Hi,
I wanted to suggest that you add some sort of report functionality, at least to the official servers! It is currently far too easy for a troll, or a troll and a buddy or two to join a server, burn/hammer a base, steal as much valuable stuff as possible and/or kick out normal players, all without any repercussion because they know they will never receive more than a temporary kick. Just today, a couple of people tried doing this and while one of them was so blatant about it he got kicked before doing anything, the other managed to keep their mouth shut for long enough that they were able to destroy an entire base, then laugh about it and spew racial slurs into the chat. There weren't enough people on the server that we could get a successful kick vote and eventually a vote to reset the server got passed, completely destroying everyone's progress and granting the troll just about as absolute of a victory as is possible.
I don't think it would be too difficult to be able to report these people by their steam ID's and have someone at Klei review the server logs, at least for really blatant trolling. People that gloat about it in chat and swear and use racial slurs shouldn't be tolerated, and I'm kind of shocked that the fine people at Klei seem to have washed their hands of this issue. I don't think anyone would want their game to be known for fostering this sort of behavior, but as it is, regular players have no recourse on the official servers. There is no moderation, either, so there's nobody there who can issue a warning, kick, or ban obvious griefers.
To clarify, I'm only suggesting this for the official servers, or at most an optional thing if private servers want to opt-in and help contribute to whatever sort of blacklist would be built up. Whether it is a system that would be built into the game itself (might be easiest at least for players) or a way to report people on the website, I think it would help to weed out the most obviously toxic people that can make the game less fun to play. Obviously private servers may have differing standards and what may be griefing to most people wouldn't necessarily be considered as such on some servers.
PS - I know there are some methods that can be used to combat griefers but most of them are not only more trouble to obtain than the average player is capable of in a short amount of time but are also as apt to be used for griefing purposes as they are to counter griefing. I don't think that sort of vigilante style is really a proper substitute for having some way of reporting these people.