As a change of pace from the standard Griezmann/Malcom/Pulisić suggestions - Oyarzabal can play on both flanks at a high level and even as a forward, and could develop into a Ribéry-esque player in terms of being a tactically astute playmaker as regards passing nous on top of having traditional wide attacker qualities like speed and dribbling ability. Reckon we need a player who's more than someone who just fits the latter mold - and Oyarzabal's ability to sense simple passes and read the game is already quite developed at 20 years of age.
Has a grafter's mentality, too (which is something you won't always find in young attacking players) evidenced by games like this (not the greatest offensive display but showcases his ability to track back and work hard off-the-ball to successfully preserve a lead at the Anoeta against Barcelona):
Also, he's developing into a consistent presence on set pieces with his headers (like the one in the video above, or the most recent one in the Europa League vs. FK Vardar):
Has been quite good in the early going through the current season (in terms of both performances and statistical output with 5 goals and 2 assists in 6 appearances):
And, he has a relatively decent
reported release clause ~€60 million - which is not prohibitive when you consider the prices for highly rated young attackers in the market:
http://www.marca.com/en/football/spanish-football/2016/08/21/57b9d771e5fdea2a3b8b45dc.html
Reckon we must find a way to further snap up some of the better rated La Liga based young-ish players when Madrid and Barcelona aren't overly interested in them. That approach has served us well with the signing of De Gea and Bailly - and other clubs in the past with the likes of Agüero, Silva, Mata, etc.