He's one of the VERY few players who can actually create his own space, take a ball under pressure and move forward without it going back. He takes on players on the outside, is always available for a pass and does his defensive duties to a good standard on top of having a good attitude and body language.
His crosses and cut backs may not work all the time but it's a low probability attack that is down to poor movement from his teammates and a last resort by him because we are absolutely shite in progressing in the middle or creating chances through actual passing.
All in all, he's played to a good standard this season. The reason why I appreciate his game is because a lot of it is created by his own ability and approach whilst playing in a majorly disjointed team i.e he's performing and doing the right things (even if it doesn't come off) despite the circumstances.
If he's our Valencia (with all the pros and cons) from under the Mourinho years, that's a 'high' bar considering the rest of the squad imo.
Of course there's always room for improvement and by no means am I 'happy' that this is his level. However, I think people are underrating his all around game because he's not certainly playing with some dominant right sided attacker and/or our midfield is dominating possession and passing him the ball with all the space in the world.