DeBruyne fits this new plan perfectly, & we don't have to play all of the new signings in every game. It may also be the case that we can get away with Yaya & Pogba vs some of the lesser, more defensive teams, if the rest of the mids put in a shift. Also, we currently have only two strikers, (if JovDeko go) & a kid. So we may play without a traditional cf in some games. Also, DeBruyne is a serious crosser & taker of set pieces, which may have been the difference between us winning & losing the title last season, plus, Bony is never getting a mention, but he is seriously fucking good imo, & DeBruyne is more likely to feed him, than any other of our players. It is a potentially deadly 'plan B'.
Pogba's assets are obvious, & he has a fairly old bloke plus a few 'box to box' or def mids to contend with, so his usefulness is obvious.