His numbers are fantastic. Lets be honest they are stats well in advance of Barkley's as well as Mirallas's. He's a natural number 10 and plays the position currently being occupied by Lookman very well. He also works hard and is a team player. His performance at Anfield was fantastic.
My two issues with him. 1) How many of his stats are massaged by set plays? 2) What with his age, could better value be found elsewhere.
That being said, for me he'd be a top signing. The consistency above is fantastic. Look at how Liverpool rave over Coutinho, Lallana or Firmino (and compare their numbers). As you've said, us with Mirallas, Deulofeu or Barkley. He's not a world beater (i.e Sanchez, Hazard Level) but looks a consistent a reliable player.