I'd prefer 4-2-3-1 but conceptually similar
- 4 in back pretty much as you have it, I'd rather Dier go with Sanchez, Tanganga, Rodon.
- 2 sitting players, 1st choice likely Bissouma & Bentancur (much more press resistant. comfortable with ball)
- Wide attacking players Son/Richie/Deki if playing higher up, Udogie/Porro if playing more midfield role
- Kane
To your question, what the midfield lacks in a world class passer, or someone who can travel with ball/beat their man and can add goals from midfield. That's why everyone is discussing that "creative" midfielder. Let me play out the scenario for you
-------------------- New GK -----------------
Royal -----Romero -------- New CB -- New LB
----------- Bentancur -------- Bissouma -----
Deki -------------- Eriksen ---------- Son ----
--------------------- Kane ----------------------
Obviously we won't get Eriksen, but it highlights the point, and Eriksen/KDB player that had the freedom of two sitting behind him gives you the option of playing into middle, then out wide or to Kane vs, being stuck with only out wide then back in.
Alternatively, if you played a speed/dribbler type that could break the lines from midfield, it would also add to the options