[Calchet]

See, the problem here is that there's really no good way I can think of to judge when someone should be allowed to give things away or ruin their lands - you pretty much have to stick to either extreme, either always disallowing it or always allowing it.

Of course, you could attempt to put together a neutral "turn review board" that'd check every turn file for unacceptable plays before allowing anything to be submit to the game server, or less extremely, a neutral "game review board" that decides when any nation no longer has a reasonable chance of winning and bans them from doing certain things, or just forces them to go AI...