I don't think he was a great club captain.
Moyes did a fine job at Everton. I firmly believe, until the end, he gave his all for Everton. Now he's gone and he's come back to poach some players, we grumble but deep down know that thats football.
Neville, on the other hand, IMO used Everton, always had one eye on pastures new(or old as the case may be). To be the captain of Everton, there can be no other club with a bigger spot in your heart and certainly not one you're competing against. His captaincy devalued Everton as a club and he was gone at the first opportunity. Hated his tweets two, bet ya players like Coleman thought he was a clowns pocket!