Worrying about who'll be captain in a few years really should take a backseat to worrying about the leadership qualities of today's captain.
It's late November, and so far, James has missed 9 out of 16 matches (league and cup); out of the 7 matches he played 2 were wins, 3 draws, 2 losses. His return after being injured again wasn't influential (enough) to set off a team fighting spirit to build on. On top of this his disciplinary record is questionable. At present, he shouldn't be captain, maybe first or second vice captain. Reece as captain being an academy product is all very romantic and sentimental, but he has brought little to justify the armband.
"Weaning" a younger player as captain is arguably being done with Gallagher. First choice for captain is not a position you still want to be doing any weaning for. You want a disciplined, clear leader, who can be expected to be fit for the best part of the season. At present, the only candidates I see are Silva and Sterling.