Hrqls: I would definitely do 6/4/off.

If you do 6/1 2/off then a 2-1 on the next roll would leave an odd number of men and therefore be a wasted roll. That would be an unnecessary gift to your opponent.

If there had been one more man on the ace point (or one less) at the start of the 5-2 then it would make no difference which you did. The 2-1 would reduce your bearoff requirement by one roll whether one man came off or two.