There isn't much I can say regarding his offensive ability since he was used as WF on sub 20 world cup, but i can guarantee that his header is the most consistent thing he possess as a resort for taking goal chances, its pretty evident he feels comfortable by doing so, not only against Ghana, but he also did this on Wigan, Chile (against Serbia), on U-21 United team and U de Chile. He just knows to find the spot and uses his ability to anticipate and beat others players, even if his chances are sparse, he takes them.
Other thing that he shown is that he's not a dummy with the ball on his feet, even if it wasn't his role on the pitch, still managed to create danger for the right wing (which clearly belonged to Bravo) trying to outmuscle his markers with a mix of speed and intelligence, his rate of effectiveness wasn't great but as mentioned earlier it wasn't or didn't feel his role as consequence of not dominating that position.
That and his technical abilities, I have seen a video from Chile Sub-20 team on a tour in Europe i guess, that he just strikes a volley with power and aim from a corner kick, amazingly. For the kind of goal scoring whore much people pretends him to be, there's more to say than just the guy who waits for the ball and just attempts to score, he is classy or has glances to become much more useful even capable of being used as a second striker, it could come nice on him thinking he's yet young and has much to learn.
PD: i still butthurt on how Chile lost, i don't think it was either Henriquez or Huerta's fault, but any type of luck would have been welcome there. There are still good names for the Adult team to consider and calling him or Castillo is something Sampaoli should think on next friendlies or qualifying matches even.