Installing traffic lights with traditional pedestrian crossings in the drop off zone has to be amongst the most stupid ideas the airport has had. I completely agree with LTNman that this will end in tears. It gives me no pleasure to say it, but it will be a complete disaster. The current system works mainly because traffic does not have to give way to pedestrians so there is a constant flow. I don't know why they didn't try to replicate that in the new zone. The distance to the pay barriers also provides a buffer against backlog there - this will also be lost.
The current system could be improved even further with a simple number plate reader and some simple flow rate logic. The number plate reader would be used to direct the first 15 cars to the farthest zone first, next 15 to next zone zone and so on. This would reduce the number of cars having to give way to other cars arriving and going to the farthest zones - which happens when the closest zones are filled up first. Even if half of drivers ignored the direction it would still be an improvement.