I mean I do think that there is a certain lack of creativity in our presumed lineup, but I don't by far think that it's as bad as it's made out to be. Tevez, for all his virtues, primarily isn't a creative force either, and we did just fine last season, even (or especially) in matches where Pirlo didn't play.
And while we probably won't have a classical playmaker starting (assuming Pirlo doesn't), most of our players in midfield and attack (bar Mandzukic, Zaza, Llorente) can create a little bit at least. Marchisio has had a few killer passes this season, Pogba can come up with something out of nowhere, Vidal has his throughballs occasionally, Pereyra is a great dribbler, Dybala & Berardi great passers.
All in all the concern is greatly blown out of proportion imo.