Would like to see
-------------Cillessen------------
Somedo--Pique---Mache--Digne
Roberto--Rakitic--Paulinho--Gomes
------Messi-------------Arnaiz
I would play Dembele, because he needs max game time until Coutinho returns. He needs to learn/relearn a lot of things. I would go with similar setup as you, but with Dembele for 65 minutes instead of Arnaiz, who should sub him at that mark. Also would play Busquets instead of Rakitić, because Busquets is a better DM and is rested.
---------------Cillessen--------------
Semedo---Pique----Mache---Digne
Roberto-Busquets-Paulinho-Gomes
------Messi----------Dembele-----
The important thing is not to conciede, so 442 is good for that (we can also switch to 433 when attacking with Roberto on the wing or 451 when defending with Dembele sliding back).
If we are trailing, bring on Iniesta for Gomes in the 2nd half and sub Dembele at some point (60th or 70th minute) for Arnaiz.
If we are comfortable with the result, bring on Alena for Paulinho.