I think team shape is absolutely pivotal to how we are likely to fare post Glasner. I am conflicted on several aspects.
We all have our views on the respective defenders in the team right now (Munoz, Mitchell, Lacroix, Richards, Canvot, Riad, Lerma. I am not including Devenny or Clyne). Do we know how good these players might be in a back four, or where their best positions might be?
Mitchell I think suits a back 4 better. Apart from that I think all would be starting with a relative blank sheet of paper.
Richards has been brilliant for us in the last two seasons. But I've never been convinced by him in a two centre back set up. The jury is out on Canvot and Riad. Lerma is a midfielder who does a job at the back in a three when needed. Lacroix looks the first pick but is he as imperious in a back two? Not so sure. Maybe Canvot can play at full back but does he get in ahead of Munoz or Mitchell? Unlikely.
Defence aside, in a back four you need to stop supply centrally and out wide otherwise opposition teams will constantly put that back four under pressure; we concede a lot from crosses as it is.
So we will need a Jedinak/Cabaye/McArthur type player which I do not currently see we have: Wharton, Kamada and Lerma seem to get bypassed as this is not their strong point. Someone made the interesting point of Canvot doing that job. It's an interesting idea but I see him as a walking red card marauding the midfield.
Munoz especially worries me: he may well not suit the shape, especially if we are then playing with wingers and he is paired up with Johnson who is unlikely to do much tracking back. The right side might end up becoming a real weakness rather than the relative strength it is right now.
But if we stay with a back three, how many teams actually make that work? Apart from some of the Conte teams and us I can think of precious few. Maybe Alonso will do something with a 3 at Chelsea next year. But it is rare.
So it is something I am conflicted about.