Charles I would first narrow down, if that's the right way of putting it, to the marked area on the right side. For me, the correct direction of play must lie here.
The question for me is: does -- put White back in the game? If not, that would seem to imply that the capping play isn't a good enough reduction. The other reductions such as points on the line a-b-c don't work so well with . Therefore I'd have to spend time considering whether should be on the fifth line.