Off the top of my head I think that Bell, Doyle, Durnan, Buchanan, Telfer, Tidser, Connolly & Sammon (who I suspect may be even longer) are the ones on the longest deals. As things stand I don't think that Durnan, Buchanan, Telfer & Tidser would be much help to us in the Championship, maybe even Sammon too? Bell's struggling fitness wise and Doyle & Connolly would probably be considered of average quality? I think it could be very difficult to move on any of them TBH.
The players that I think we would want to keep would be Dixon, Miller, Gomis, Longridge & McManus, all of whom are out of contract in the summer I think so will be difficult to retain.
That leaves us with McShane, McLean, Leitch, Laverty and McMillan from McKinnon's tenure that we'd be in a position to release in the summer and I think it's fair to say that they'll all have to go to allow us to get better in.