This is a simple how to that will hopefully reduce the sheer amount of retardation that most multiplayer hosts seem to suffer from.

Brick Limit: 2,000-3,000.
ONLY Invincibility and Respawn Anywhere should ever be enabled in a roleplaying server.
This includes disabled Building Damage.
No max vehicles per player or auto removal timer.

Brick Limit: 1,500-2,000.
Respawn Anywhere, Explosions, and Invincibility should be enabled. All others disabled.
If you want crashing in your racing, disable Invincibility and keep Explosions enabled, otherwise, just disabled Explosions to.
2 Vehicles per player, 1 minute auto removal timer.

Brick Limit: 1,000-1,500
Only enable Weapons and Explosions.
Enable Respawn Anywhere if you're running a mod map otherwise you may be unable to respawn.
2 vehicles per player, 5 minute auto removal timer.
Would also be smart to have a vehicle whitelist to prevent spamming OP vehicles.

Even as a retarded server host who can barely handle the easiest to ban trolls, a good rule set will 9/10 times ensure a playable server.
An additional tip, give your server a password and put it in the server description. It will reduce traffic into your server but will better defend against the even greater ♥♥♥♥♥♥♥ who troll.