For what it's worth, here's my shot at recommending players to leave:
Robles: He's been a good player for us, despite being treated shabbily by Koeman and being backup since Pickford arrived. He deserves his chance to be a #1 somewhere else, and I wish him nothing but good wishes.
Stekelenburg: Frankly, the only reason he joined the team is because both he and Koeman are Dutch. What a waste of money. It's time to go.
Martina: We should never have brought him in in the first place. Time to leave.
Williams: He was supposed to be our leader at the back, but he's had a hard time this season. I put that down mostly to lack of motivation due to a lack of confidence in our managers. Too much water has now passed under the bridge, though, and I think he should leave.
Mirallas: It's easy to forget he's still on our books. A poor attitude ruined his chances to make a comeback, and he should most definitely leave.
Bolasie: Over-rated, in my opinion, and not of the caliber we need. Bring back Lookman.
Garbutt, Browning, Pennington: We all want the youngsters to succeed, but they really haven't. It's time to go.
Rooney: For his own good, really, he should accept an offer in the US or in China. The only reason he would play in our first team is nostalgia, and that's not conducive to success.
Sandro: I'm in two minds over this guy. Given the chance by an inspiring manager, I do believe he'll prove to be valuable. His track record over the last year has hardly been inspiring, though. Maybe leave, maybe not.
As for players who most definitely NOT leave:
McCarthy: The injuries are not his fault. We supported Coleman through his leg break, and we should do the same for McCarthy. He's the leader we need in midfield.
Niasse: As a super-sub, there are few better right now. His attitude is contagious.
Jagielka and Baines: The younger players can learn a lot from their experience and loyalty. There's little point in pushing them out.
Klassen: He has a lot to prove. You don't get to be captain of Ajax, especially at his age, without being something special.
Calvert-Lewin: He's like ivy growing in the garden. The first year it sleeps, the second year it creeps, and the third year it leaps. I'm predicting this will be his breakthrough year.