I'm a little underwhelmed so far, just doesn't have great dribbling or vision. Just seems a nice player for playing out of a press and making some 1-2s, a slightly better Wiljandum.
I think this game has shown us that he is simply not a great attacking talent. He is good at delivering progressive passes and progressing the ball himself by carrying it, but his attacking instincts are mediocre. De Bruyne or Xavi or Iniesta of course are all far better attacking players. For me it is clear that De Jong either has to be a CDM or be fielded with a CDM and a very competent midfielder in attack like Iniesta/Deco/De Bruyne.