If they had stopped at 15 it would have been sensible. Last season they had an incredibly settled side with great momentum by the end of the season. Why they didn't try and keep as much of that together is a mystery as they showed in the FA cup they could dismantle PL teams too. Spence could have been attainable on loan from Spurs, his move there has been a disaster for him. Garner and Davis might not be brilliant but both were settled and crowd favourites. With the resources they have both were very attainable. Cook and Colback were the 2 who don't have the legs for PL football but both could have been grand to have around for experience.
Like at Chelsea I can only imagine how difficult it has been to organise training with such numbers, there is a reason top teams like to have tight squads.