I agree with OP 100%, "you make people leave".. it's true, I was in the server few days ago and I got lamed by 4 guys using 2 or more firetrucks to spray me.. I didn't stand a chance and I didn't want to go kill other people then them cause they were few of the only "good" players in the server, sure I could go around killing random noobs but that's no challenge.. haven't visited LW since then -__-
Virtual worlds: just do it, add them for races. I even got an idea for people who WANT to block races, what about adding something so you can join a race but as someone intending to block races, you'd spawn in the same world as the racers and have lots of big vehicles like firetruck you can use, then there is a checkpoint on the radar, say there are 10 checkpoints in the race and the player who is leading the race is at checkpoint 2 it would set the objective on the radar @ the 5th checkpoint telling you to go there and block the race and prevent illegal street racing, as soon as the race leader hit the 5th checkpoint it'll set the second checkpoint at checkpoint 8.
Perhaps this could be a job.. police job? checkpoint somewhere in lvpd where you can see if a race is going on and join if there is? And you can gain $$$ if one of the racers bumps into your car
the more damage done to your the racers car the more $$$ you get (or something), maybe you'd have the option to spawn 'block cars' like dumper, firetruck etc whenever you want.. but you wouldn't be able to use any weapons.. what about being able to have multiple races at the same time so the job is more often available and you can choose which race you want to block, also there should be a maximum of X blockers.
Just an idea I quickly came up with, will obviously have to be better thought about..
VC-MP: 
