Ozil is one of those players that makes football worth watching. Sometimes he does some unreal things with the ball, like a no-look volleyed backpass, or a threaded pass through a crowd of opposing players to find Giroud like a needle in a haystack. I know he gets a lot of shit for being "anonymous", but we're much worse without him in the team. If Coquelin is the player who gives us midfield steel and backbone, then Ozil is the one who gives us fluidity. He makes the initial passes that become goals, every time. Hopefully he gets back the confidence he had at Madrid, and goes back to being one of the best midfielders in the world.
He had a few injuries (and one long one midseason), so it's hard to judge how his 2nd half has been. It's clear that he's capable of so much more, and we'll finally see that now that he gets a summer without a tournament and an injury-free preseason in a settled squad.
Here's a good compilation of what he's been like this season: