I like that he's clear with what his wants and can very clearly see the issues. My worry is that he's got a lot of work to fecking do, some of it he can't control (player personnel), some of it I'm not sure will 'work' well enough (midfield two) and he's got to do that whilst trying to win games and not lose morale/support.
You can blame the back three for being super cautious and poor on the ball but you can't make de Ligt an elite passer and Martinez a great channel defender. Except, even if he can get a back three to be good on the ball, relying on a midfield two combination of Ugarte (who holds his own), a developing Mainoo and/or Casemiro/Eriksen/Bruno to be receiving balls on the half turn or find space there when teams hold their position and don't press the defence is already big task in itself. He'll need a couple of Fabregas, Matic, Kante, de Jong like talents for that to work and even then, it's a risky strategy especially if you already got Rashford, Garnacho and unproven strikers in Hojlund and Zirkzee in the forward positions. I'm going to give him time and I understand the need for him to rotate and find his own path but I'm tired robbie.
I honestly think he can do a quick fix by playing Mazraoui as RCB, Dalot at RWB and Amad as one of the 10s. That's a very strong right side with all the passing, defending, attacking, athletic and ball progression you'd want. Rotate Yoro in at RCB to manage his minutes. On the left I'd play Malacia or whoever is fit. You're hamstringing yourself spreading the talent to accommodate other positions and players.