Yeah no way should dani ceballos leave! He'll be a very valuable squad member for years to come. The left back and center back situations are interesting.
2 of Fran, Miguel, Mendy and Davies will be at the club. I don't think the club will want to get 2 new guys. I suspect if Davies comes one of the squad lbs leave, if he doesnt come, nothing happens there.
At cb Nacho is captain and might stay another season, but with reports of Yoro and now the return of Rafa Marin suspected too I dont know if Nacho stays. Alaba is still only 31 despite looking a lot older this season and has an ACL injury too. Rudiger and Militao are certain starters tho.
Where do Endrick, Mbappe and Guler get their minutes from god only knows. Endrick likely goes to Castilla first, Guler has a loan possibility (or sell brahim). And Mbappe is a starter so joselu and rodrygo lose out on minutes.