If we sold Baines now, no team in the top half of the league would buy him to start for them. His stock has fallen dramatically due to injuries.
Nowadays, without a decent left-sided partner and without him contributing goals and assists, he's rank average, sadly, and he'll only get slower and less effective from here.
Jagielia is finished, Barry has 6 months left then he's gone, Williams might get to the end of next season in the starting XI, but then he's gone too. Stekelenburg should be sat on the bench either from next month or the summer, but preferably sold asap with a younger keeper providing backup.
We have a lot of players ready to be moved on, and that's not including the younger-but-still-useless gang of McCarthy, Gibson, Besic, McGeady, Kone, Niasse, Robles, Oviedo, Lennon and arguably Mori, Mirallas and Deulofeu too. Barkley can be added to that list too if he doesn't pull his finger out.
Essentially, 80% of our squad is absolutely near good enough for a team with ambitions of even a top half finish.