What he has is a great foot for passing, and somehow decent vision that combined with that foot appears to be better than it actually is.If we could mould him into a number 6 that would be interesting. He seems to have the passing ability and vision for it. It's the defensive and positional side that he will have to pick up.
If Ander had a right leg as good as Pereira he'd look like a discount version or Kroos. That's just how good his leg is, but he's been relying on that quality for far too long, I don't think United have the time luxury to develop his vision and decision making to the level a United midfielder should have, let alone also improving his defensive game at the same time, it seems reaching too much.