I've seen Jeffry in those CL matches vs Arsenal and Juve and he showed a lot from Yaya's repertory with his physical tackles, runs and shots. It was a bit raw but only a bit and I persume he'll improve, expecially in a team like ours.
I'd like Toure to stay if we would be able to buy only Pogba or only Kondogbia to that position.
I remember Yaya being impressive and very effective as a box-to boxer just 3 years ago, he could help the defenders, tackle the ball and then run with it to the other end of the field, dribble and score, but is it the case now? is he still as good? No. Is he as motivated to... even play? No. Then why keep an unmotivated aged player on his way off when we could buy 2 more proper talented players for his position?
Yaya isn't as good at CAM position, he could be at times, but it happens rarely. Remember this season, he couldn't do anything playing CAM most of the time... Surely we need somebody who is 'fluent' at this position. And, obviously, we basically need somebody younger.