It seems that the problem of timing down on tournaments and other unsporting behavior has no solution yet. I did a quick search on the forums and found no similar suggestion yet (although I did expect to find one!), so please forgive me if this is a duplicate topic.
I believe it would make sense to launch an experimental system where every player could exactly once "vote" on another player, to either increase or decrease their reputation. Increasing may give two points, decreasing would reduce the reputation of the voted player by two (again), and the reputation of the voting player by one, to discourage pointlessly doing it.
This would hopefully result in a decent reputation system, where a player may be categorized by their behavior.
This would allow excluding "bad" (in the sense of behavior, not chess skills) players from joining your games, sending them warning messages below certain thresholds, and for unusually bad reputations, the player may be automatically flagged for moderator review and/or excluded from joining tournaments.
On the other hand, "good" and friendly players would be valued by the community. This could be a strong factor in awarding LM titles, maybe even a reason to introduce some sort of reputation based award or a new ranking list. Their votes could have a larger effect on the voted player, perhaps they could get additional privileges.
Hopefully this would help fight unsporting behavior, but it would at least give anyone a scale whom they are playing against, and what they can expect from their opponent.
What do you think? Does this make sense? Are there flaws, or things that I missed?