I think the 1v1 defending area he is really good at. Certainly better than I expected.
He is really good under pressure with the ball, his dribbling is excellent which I think will be a key part of the team growing into a better possession team. He'll allow us to stay on the ball for longer, even while being pressed, I think. He contributes to the build up of attacks better than people give credit for, rather than necessarily being the one who gets assists or the odd goal (as Doc did pretty effectively). Think people are getting too hung up on goals and assists with him anyway if I am honest.
He's obviously very quick, which is a bonus in many phases of the game. I'd like him to be braver attacking 1v1 though, think he doesn't take players on round the outside as much as he should (although usually because Neto and Adama want the ball wide and do it themselves).
Weaknesses wise - his aerial ability concerned me from the start but has improved somewhat in fairness and we are protecting his weakness better. Big issue at moment is his tendency to switch off costing us goals, been too many even recently, which by start of next season he needs to eradicate. With time and learning the set up better he can do that though by then.
We sold Doc for £14m and bought him for £27m. I struggle when people don't see him as a significant upgrade on Doherty, if I am honest. I think he is just a much higher calibre of footballer. People keep going on about us not being fun enough to watch but he will contribute to us being a better team to watch in the long run.
He's probably one of the ones I am most looking forward to watching live from a) an aesthetics point of view and b) to see whether he is better or worse in person!