^^^ I think you're right with A and B, and I would like to see C happening too!

The main problem I think with arrangers is that they are still too much on the traditional side, despite various attempts, they are yet to combine MIDI and audio in a way that is relevant to today's music. If they only introduced a more flexibility and randomness in the way styles work for instance... Yamaha is making steps though with Genos. But I think it is still a along way to go.

It may be different across the map, but there will always be a place for arrangers. I just hope they will manage to stay relevant, so that more people will become players.