The match Brazil VS Spain of the Confederations Cup is a good match from Paulinho. You could watch the full game it if you want.
His main ability are his runs trying to infiltrate the area looking for goals. He has good control of the ball, can dribble and can do good passes (although he can't dictate the rhythm of the game). He can help with the construction of the tiki-taka by giving options for others to pass, he can find or create spaces while doing it. His finishing is great, he is a player that usually dont fear the big matches, he can defend really well, is tall and isn't slow because of it. He is one of brazil's coach favorite players (Tite managed him on Corinthian from 2010 to 2013). Even with Fabinho (Monaco), Fernandinho (City), Allan (Napoli), Rafinha (Barcelona) and other good CMs surging (Wendel that PSG is buying right now, or Douglas from Manchester City), he is there as the absolute starter for Brazil (41 games).
I cant say for sure that he can do his best on tikitaka, but he is not a player like Douglas (RB) that nobody on Brazil understood why Barcelona was buying him. The mistake is that he iss too expensive and too old to be a normal aquisition, BUT, he does have quality to increase Barça's game.