I think you're underselling mason and benteleb. Mason was very very good at the beginning of the year. In terms of number of games played, he's still a young player due to the number of injuries he's had and I believe he can still improve. Especially considering he has only been a CM for a year and a half now. Benteleb obviously has potential, shame he has been injured but he seems determined.I think you're bringing sentiment into it a little too much. I agree that we shouldn't be kicking out players who deserve a shot unless necessary - but the list you gave there are mostly general CMs as opposed to specific CDMs in the mould of Dier himself.
Dier - number one choice, of course
Dembele - thriving playing alongside the CDM and carrying the ball forward
Carroll and Winks - CMs, and neither appear to have particularly good defensive capabilities
Mason - seems like a good utility player, and has some CDM-like qualities... But I think his ceiling may be about as high as his best displays last season (which I think we could aim for better) and is injury prone. Would rather he slotted in at CM rather than CDM to be honest.
Bentaleb - disconcerting to see his current form post-injury, but have faith he'll come back well. Of these listed, has the best attributes for playing CDM. Would have to see how Poch uses him moving forward.
So considering all that, I think only Dier and Bentaleb are good fits for the CDM position - but the latter has hardly been covering himself in glory recently.
Dier, of course, can also be one of our CB back ups, meaning that depth in CDM is key for times where he needs to be slotted in the back.
TL;DR - if we're in the Champions League next year, I think it's key to add another CDM in - as the long list of midfielders you mentioned are really fighting it out for the other position in central midfield. At least they are if we want to maintain our excellent defensive showings.
I actually am not a huge Carroll fan. If we had to get rid of someone id say him. He's so suspect defensively and isn't so good offensively to make up for it. If we had the chance to relate Carroll with someone obviously better I would but otherwise I'd be happy to keep him.
Winks deserves a shot and died and dembele don't even have to be talked about.
