I think you need wingers snd full backs to play 5 at the back with 2 strong players in the middle, why I don't like 5 at the back cos it's based on 2 central midfielders not 3.
Nothing stopping you having 3 in midfield with the 5* at the back. Say we sign Gana, him + Onana + one of the wingers we have now playing or Iwobi. Then you have DCL and Dele or Iwobi up top.
If you play Iwobi off the striker when defending we should be able to form a 541. Going forward it would be more of a 3142. Obviously Dele would show more attacking wise so there is a thought where you would perhaps use Iwobi against the top teams and then Dele against the ones we have to break down.
The problem is with that is we would have Dele/McNeil/Gordon/Gray/Townsend/Iwobi all vying for 1 spot - perhaps 2, Which is plainly bad recruitment if that is the case.
If we want a system to help get more of those on the pitch then we need to revert to a 442 or 4411, make sure our full backs are more for defending than attacking, but then you are committing to 2 in the middle with a possibility the the no 10 comes back to make it a 3 in the middle of a 5 man midfield.
Whatever we are doing now doesn't work as the overlapping full backs take up the space where Gray/McNeil and Gordon might do their best work and none are good enough to boss it from the middle.