Since this incredible update, I've had an idea for an object that can links two tow hitches from both of its ends, so you could simulate a tug-o-war between two (or more) vehicles. Of course not every vehicle was meant to have a back AND front tow hitch, but it would give the ability to expand on this type of scenario. Think of 3 different spec D15s all facing the same way all linked up, versus one 75+PSI turbo diesel T75 facing the latter. Just think of all of the different possibilities!
That sounds like a good idea. How long would this object be? Would it include any slack and/or springiness? (eg behave like snatch strap vs rope vs a metal bar with two hitch receivers) --- Post updated --- I started working on something based on your suggestion: http://www.beamng.com/threads/barebones-mod-for-coupling-two-vehicles-together.28972/
I like the options, why not all? The biggest concern is the ability of handling large amounts of torque to prevent it from breaking. But also, that will be defined by the material that it is supposed to be (rope/chains/etc)
A snatch strap would probably be best so you don't have sudden jerks every time you take up the slack.