The problem with moving things into arc.arc is that it increases the difference between anarki's arc.arc and pg's arc.arc, which makes maintaining anarki when pg updates arc.arc a PITA. I speak from personal experience. It may seem like a good idea to you to move stuff into arc.arc, but it makes the community's life harder in the long run.
I'm not proposing hacking existing functions. Basically everything should be able to be maintained by running a diff between the 2 arc.arcs and pasting the extra functions in the Anarki version into pg's new arc.arc. What difficulties did you encounter last time?