I think Paulinho is indeed different from what Barcelona midfielders, André Gomes included. Gomes is really slow, like Ganso, he is a class, elegant player but his football simply doesn´t belong to this era, because he´s just too slow. Paulinho will add physical strenght and pace, his pass is not great, but he will accelerate and drive the team forward, also having some decent finishing for a player of his position.
Honestly, I have no idea if Paulinho will succeed in Barcelona and like I´d have signed Matuidi before him but yes, he brings a different element to this team. He will probably fight with Rakitic for a starting position. Considering how bad Rakitic has been since last year, he could win it.