You're right. I know that feature is lacking on normal servers right now anyway, and even without it, having a specific server without all the road restrictions you mentioned would already be a huge improvement.
Fortunately, I haven’t personally seen the issue of different convoys departing from or arriving at the same city at the same time, but I can only imagine the chaos it would cause. I suppose the chances of that happening are low, but it still exists. Rather than implementing a booking system, which might be difficult to set up, maybe the VTC ET/EM members could check the already planned convoys and try to avoid overlapping cities. With such a large map, that shouldn't be too difficult, I believe.