Since airports grow bigger and bigger, more traffic uses the airport. This will make parallel taxiways necessary.
Good examples are Amsterdam Shipol and New York JFK. One taxiway is normally used for clockwise movement and the other one for the counter clockwise movement.
In the current version, the traffic seems to search for the shortest distance between the runway and the assigned stand. This is only halfway real and leads to traffic jam, as multiple aircraft await the crossing/pass of one single aircraft and delays in any kind occur.
Therefore I would like to see a ground movement management toll/controller implemented, which allows to set specific taxiway directions and other rules (e.g. max Wingspan).
I hope you guys have the same feeling.