Kone, Niasse, Rodriguez, McAleny, Gibson, Pennington, Browning, McGeady - have to all intents and purposes been frozen out the squad anyway, thats 8 players right there that if they never showed up for training again - no one would actually notice.
Oviedo, Deulofeu, Cleverley, Jagielka, Robles, Valencia are basically only seeing game time - because the manager has no better options due to a terrible transfer window this summer, IF he can do he will bring in players ahead of all these in their positions and from that point onwards they are all in the boat with the Kone's as far as being totally out the squad. Thats another 6 players right there.
Mirallas, Mori, Lennon - seem to be liked more than the ones above, but none of them seem to really be a fit for what Koeman wants - so yet again depending how many we bring in - all of those are on borrowed time at the club - theres another 3
McCarthy seems by all reports that he wants to leave - probably the only player i listed that Koeman would choose to keep hold of in ideal circumstances.
If we bring in 5-6 this window who go itnot he first team or squad, and with us having 4 lads who have started getting into the matchday squads from the academy (DCL, Kenny, Davies and Holgate) then thats 9/10 spots we really need to free up at the latest by the summer - and assuming we bring in 4-5 in the summer that would mean we need about 13/15 spots - given we actually already have at this moment a very large/bloated squad (Huge for a team with no european footy) then seeing 18 players out would actually be needed, much the same way that the rs have done this under Klopp