Make my tactic a success!

Hey there, I've decided I'd try and master the game yet again after so many failed attempts! Inspiration taken from the in depth Cleon thread Building A Tactic From The Beginning And Maintaining It Long Term. Anyway...here's how my new tactic currently looks:

https://goo.gl/photos/YGZWcmJjfLmLLKKr6

Now as you can see or not see if my img doesn't show up, I've gone for a 3412 formation. My team instructions are retain possession and run at defence, this will hopefully be my identity at the club.

I've chosen a flexible team shape although I may consider changing that to structured as I'm not sure if I want my central defenders to be used in the transition phase.

I've chosen a standard mentality because I like the balance of attack and defend, also I may shift this to either side of the spectrum depending on what I see as the match plays out.

My biggest concern about this tactic is the space down the wings if I get overrun or the space I leave open if I over commit. Currently I have the roles set as wide midfielders on support duty but I'm now wondering if defensive wingers would be more appropriate, especially if I line up against a wide 442.

Against formations that employ an AMc I will look to my DLPd man mark him to reduce his impact.

Another concern at the moment is how spread apart my centre backs are so I might look at resolving this by adding play narrower in the team instructions. Unfortunately a knock on effect may be that this reduces space for my players to play in which could hurt me against tight compact sides. One possible way to overcome this might be to exploit the flanks in the team instructions.

I'd love to hear some of your thoughts and advice on this tactic and I'll look update this soon with more details.