Keep the "follow the greens" system. It really is the best I have seen in 30-something years of flying.
It was developed from the switch systems of British Railways, (yes before all these rail track chappies) so had a good pedigree even when it was first introduced.
The BA people (probably not the line pilots who use the system) have a very small problem and they wish to fix it with a total disruption to the rest of the worlds London bound aviation. An acute case of technical arrogance.