Xhaka would change our team a lot. He's far better at controlling play than any other midfielder we have at the club, while actually having the physical attributes necessary to solidify our midfield. Elneny would actually be a relatively good partner for Xhaka. I've lost count how many times our ability to create chances has been offset by the slowness and lack of ingenuity in our build up play. It's been sh*te for a while, and I can only think that people do not watch us play enough to assume this narrative that we're all midfield. Right now, we aren't anything.First, I quoted that his reticence from shooting was a directive from Wenger, where he is being told to not do as much attacking as he normally does.
Second, to talk about problems in your attack due to your CM when you play with 4-2-3-1 is rich. His job isn't to do that, probably as a result of Wenger's directives from the first point.
Third, he's not your deep lying playmaker, he's a CM who makes sure the team works. But with your setup, neither one of your CMs really should be directing play. Also, he does have the eye for a good pass, games against Hull or Watford show as much. Now, you might say "who cares about those teams?" Well, it's been stumbles against teams like that, that have undone your season.
Fourth, yes teams can have multiple problems. Your midfield isn't one of them. Your CBs and strikers are.
Xhaka isn't going to change your team that much. Having someone who can make your opposing team's defenders think twice will open up the passing lanes, because teams just have to cut off supply to your forward and they have you done for, especially since your players then return to trying to "walk it in." Your defenders don't dominate and get beaten on set pieces if they're not making horrible mistakes themselves.
Midfield definitely is a problem at the moment. The entire centre of the pitch from defence to attack is pretty weak if you ask me and that includes midfield. We have ball-winners who can't pass well; a player who wins tackles and passes well but is old, injured and past his best; a B2B midfielder who thinks he's an attacking midfielder; 2 midfielders of supreme technical ability who are not defensively strong and one of them is injured all the time. And then there's Elneny, who is decent at all these things but excels at none of them. So far, I'm also underwhelmed by his tackling - other than that, he's been a revelation in terms of actual central midfield play.
He alone does not solve the problem in midfield however. Coquelin and Elneny is a stable midfield. It's also very bland, and not one I expect to be capable of helping to win a league/CL. I'd be surprised, put it that way.
I agree that strikers are a pressing problem. I'm also not too convinced by all our defenders, but I think that's less to do with personnel and more to do with a system that literally only involves frantically getting back into shape. But our forwards are wasteful and it is a problem that must be addressed immediately. But I can also guarantee that if we only signed a striker, then next season we'd still have problems in midfield and our build-up play will suffer from not being as good as it should be, and it will only be good if Wenger signs another midfielder or someone from the academy magically becomes the guy we need to initiate attacks from deep and show the tactical nous needed for the position along with it.
P.S. It's not rich to suggest that your CM actually contribute to your attack somehow in a 4-2-3-1. Playing with 2 CMs with no discernable attributes that can help an attack become more potent (doesn't mean just going forward either) is pointless and leads to a team that is literally divided into two. If your midfielders cannot contribute sufficiently, then your attack will suffer - unless you're a defensive team and you're set-up that way by deliberate design. And if Wenger's directives are that his CMs do not contribute (which I highly doubt) then he is being even more foolish than I thought.