IMO a mistake being made by a few posts in support of retaining Ozil, seems to be that they are basing his importance as seen under AW's style of play through the middle, and not his lack of impact or importance as a result of the new style of play under Emery.
IF we were still playing a centrally based style of play then perhaps we could justify the 350k/week wages, but the simple truth is that a player of Ozil's style and quality is a luxury under Emery's style of play. He neither sees enough of the ball in transition because the new style by-passes him at CAM (hence the reason he was tried on the flanks), and when the ball does go central in the final 3rd we do s in order to finish attacking moves with strikes on goal, not to recycle the ball via a passing playmaker.
For Ozil to succeed in the new style he needs to reinvent himself as a player to show more end product in goals scored as our 3rd goal scoring role, rather than being the playmaker with the assists. He needs to embrace that responsibility himself as opposed to looking for the pass.
For mind Ozil's best opportunities in the new style probably rest in 3 shapes seen of late - the 4222 seen v Fulham as one of the twin AMs played behind the front 2; the 3421 again as one of the twin AMs played behind the CF; and the 3412/352 playing in behind the front 2.
Again the question for Emery and the club is when all things are considered equal do we stick with the new style in the 4231 that marginalises our highest wage earner and plays one of our 2 starting quality forwards out of position, or do we twist for the sole purpose to get the best out of the key players and the team for this season with the view to regain top4, and then to sell the misfits and continue to rebuild in the summer once having regained CL qualification?
I still think Ozil can succeed as a wide playmaker from the flanks (so long as we do not expect him to play as a winger looking to get beyond the defence on the ball), as his movement inside is natural when using an overlapping FB/WB. As such I think the decision to try him from wide was still correct, except that it doesn't work to full impact when we were having issues at CAM and CM at the same time which exposed Ozil's lack of defensive impact in support of his FB on either side of the pitch. IMO Torreira resolves most of the midfield issues.