John Stones has played 24 games for Barnsley at right back and never in the Premier League. Tony Hibbert has represented us 259 times and has played at centreback under Moyes in an emergency. Would you rather play two academy players (Stones and Duffy) instead?
Heitinga is probably going. If he isn't then he was our player of the year not so long ago and was good enough to play in a World Cup final. Playing regularly and having two central defenders alongside him come help him to rediscover that form.
I think Naismith could be our version of Kuyt and score some important goals. He has struggled to adapt but he's been asked to play in a new position and he hasn't featured very much, so it's understandable.
Gueye will find a new club in France I expect. If we're going to have players like that in the squad they need to be contenders for a starting position otherwise they might as well not be there.
Osman broke into the England squad and scored only one fewer than our second top scorers (Mirallas and Anichebe) in all competitions, despite playing for much of the season in a deeper role. We might as well try and accommodate him in the side. And if Mirallas or Barkley played in front of Coleman they're likely to leave him exposed, which will mean that he won't be able to get forward as much. Ossie could do for him what Pienaar has done for Baines on the other side.
What is your amazing idea? Get rid of Heitinga, Naismith, Gueye and Osman? We might get about £8m for the lot if we're lucky. That would cover Fer's transfer fee. Now how are you going to cover the other three positions?