Update: Third Suggestion. If the dber makes a db kill he gets frozen for 5 or 10 seconds. And he can be killed while being frozen.
luv it.
Also this doesn't always work, let's say a skilled player is somewhere isolated, and some db nab comes to fuck him up because he's too scared for a fair fight, he doesn't get punished that way because no one is around to slaughter him while he's freezed.
The idea itself isn't bad though, but I can't help being sceptic about it's effect. I don't think this is gonna change the current situation, probably the db'ers go to the suburbs to take their chances, but the problem isn't really solved that way. Would be cool like mentioned before if the db'er gets a cashpenalty and -1 kills on his stats, the only problem that stays is the 'db to low life and shoot you off like a dog noobs'.