Gotcha. I would normally just call that handlining. And FWIW, a lot of people do handline that last Subway rap, but it is still very much rappel-able. I'm in the camp that I'd rather carry the harness for that kind of thing because I feel the cost to carry it outweights the potential injury for not using it. Just slipping on a wet rock would easily be enough to lose grip on the rope and a fall there could be fatal or at least very, very painful and expensive. Also, the new anchors above the Subway are definitely NOT suitable for handlining. They were put in because the others are getting more and more inaccessible due to the changing log jam situation above the waterfall room. I know we're not really talking about the Subway, but it's good that more folks hear about that so they don't go unprepared.
For the pack lowering at Crack in the Wall, you don't need all that much. I always carry 50 feet of 3mm paracord when I backpack and we used that with plenty to spare. Be sure to go to the lower opening though. When you first drop down the crack, there is a ledge with lots of rope grooves. If you go a little further through a short narrow section, there is another ledge without rope grooves that is way closer to the ground below and much easier to lower from. Saves you work and saves the rocks damage.