Moyes has already stated that he doesn't want to throw Barkley in there too soon. He has the ability but mentally he isn't up to it yet. He also had a horrible injury last year which put Everton's plans for him into disrepute as he would of been a first team regular by now had he not had that, I'm certain.
This season is a learning curve for Barkley. To gain match fitness after his injury, get a few minutes game time at the highest level and improve and learn through as much game time as possible at academy and reserve level. Moyes has stated he will use him towards the end of the season so he could be used in the remaining games. I think he's done well with Barkley. He came into this season with a hell of a lot of pressure on him because Everton looked like they were going nowhere in the summer and the fans needed someone who could give them a lot of hope. He made a terrible mistake against Blackburn and was taken out of the firing line, which was needed as it affected him mentally. I think Moyes has done the right thing with Barkley as there hasn't been a huge need to play him as much as there was with Rodwell when he first came into the picture as we had a terrible amount of injuries then. Barkley will reap the rewards this season and I think he'll become a first team regular next season and make a position his own, whether it be out wide or through the centre.