Just my OPINION but id keep Walker, i just think he has been unfortunate with injuries this season - i dont think he is over the hill just yet and has plenty of potential IF he can stay fit once back from injury, possibly playing in at second row - the final part of the season will be vital for him !!
Raynor - Still has the pace and strength to be a quality winger, still one of the best IMO, just lack of the ball in first half of season to do ought
Ainscough is a keeper, young lad with a bucket full of passion, great potential - just again unfortuante to get injured - but dont thin he has been given a full chance yet.
Ah van should be tried at Stand off, if ainy and raynor fit on the wings, and jeffries at 7 - Briggs is ok but i think could be utilised better as a loose forward.
Herbert - not too sure, with the results and the way the team has been playing not really given space.
Kearney - definately a keeper, back in at full back, missed his creativness through injury
Royston been a good stand in at FB for kearney but could always be pushed to centres.
L'Estrange - again no brainer for me - defo a keeper
Halley/Finnegan - need to be given a chance now with injuries to prove their worth
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As someone did mention forwards:-
Lynch - although i like the guy and has been a good player for us maybe the time has come to move on ???
Donaldson - not been given a fair crack this season IMO good young talent, who showed lots of improvement before getting injured last season
Koppy/Whitehead - Play hot and cold i feel but defo worth keeping for years to come as we need to keep the english youngsters, to save quotas.
Langley - although spends a lot of time on the sides when he is available he plays with the pride and passion we need in the squad !!!