Some nice ideas, hope the mods can find something useful.

I was thinking of the idea to place bear traps on the ground to break legs of players or zeds that step on it after placement. Especially for good to get players who constantly clear out all the good weapon or food caches.

nice idea, but it's not feasible atm. No one in their right mind would wait trapped until they get robbed or fall down and break their legs if they could just escape by switching servers.
Let the devs deal with combat logging/ghosting/server hopping first (hopefully by getting rid of that hive system)

Yes, this would make the game more interesting, and might make the use of the handcuffs more probable...

More ways of entrapment of other players would be fun, like you are able to setup some kind of place to loot wich is actually a trap....wich locks the player for a certain time....

Instead of killing it would be robbing