He was one of our top earners (supposedly on £120k a week) and came up with 6 goals and 11 assists in 123 games. It's reasonable that we wanted more for that money.
He is talented but it was never really clear what his best position was and he gave the ball away a lot.
To be honest I suspect the full back situation is one Moyes is reasonably happy with if everyone's fit. We have 2 decent (albeit not great) options and a 3rd less decent one for both positions:
LB: Mykolenko / Branthwaite / Aznou
RB: O'Brien / Garner / Coleman