Id say he would actually improve our squad.  If we could sell Keane for 35m and get Silva on a free that would be great business allowing us to put all of those resources into the positions we need now, and buying Braithwaite a season or two. 
Silva is starting in the Champions League right now, he would immediately improve us. 
Also, I dont get the people saying "6th place is impossible, 8th is our best hope".  Theres literally 3 points between the two this season.  Maybe the rest of the league falls off a cliff and it becomes a bigger gap again, but that seems unlikely since the rise of Wolves, LCFC.  The move from 8th to 6th is nothing compared to the move from 12th to 8th.