Virtanen has a shot that will beat NHL goalies. I'd love to see him get more time with some line mates that can set you up. Virtanen and Pettersson could complement each other very nicely if they clicked. Hopefully with the Sedins retiring we'll see some real experimentation happen with the lines.
He has not demonstrated the accuracy control necessary to consistently beat an NHL goaltender. It's a pretty big part of why he only has 17 goals in 140 games.