I wonder which side Greenland, Iceland and the Falkland Islands would pick.
Iceland and the Falklands would likely be respectively -9 and +12 from Japan.
Greenland is probably the best reason to keep Greenwich as the reference time zone. :) Most of the population (so to speak) is on -13 to -12. I have no idea if the people there have more ties to continental Europe and Iceland, or to Labrador.
There is only one good alternative, which would be to place the date change line in the middle of the Atlantic (between UTC-3 and UTC-2) and the fundamental time zone in Japan or somewhere Australia (UTC+9/UTC+10).