Indeed, we can't overlook De Bruyne's importance at Man City. All these temporary alternatives are just placeholders for him. To go the distance in the upcoming crucial matches and defend their hard-earned titles, De Bruyne's return is vital for Mancity.
So far it has been very visible that Manchester City's midfield performance has declined quite a bit since De Bruyne suffered an injury. It cannot be denied that De Bruyne has been a very important player for Manchester City all this time.
De Bruyne is expected to be out for 4 months and he will most likely recover from his injury in January.
So far there has been no big challenge for Real Madrid in facing opponents in the Group stage and even Napoli, which was previously considered to be a balanced opponent, was unable to face Real Madrid even though the match took place at Napoli's home ground. It is almost certain that Real Madrid will be at the top of the Group standings because their next opponent will be much easier in the remaining matches.
We will see after the group phase ends and who will be Real Madrid's opponents, the round of 16 to the round of 8 will be even more competitive because they will meet strong teams before heading to the semi-finals. If the two teams you mentioned can advance to the semifinals, that would be much better because it would produce quite an nerve-wracking match.
It was predicted from the start that this group phase would not be difficult for Real Madrid, because Napoli also experienced a fairly drastic decline in performance after they replaced the coach and the other two teams, Union Berlin and Braga, had quite a difference in quality below Real Madrid.
And for the knock out round, there is quite a lot to look forward to because currently many of Europe's top teams are starting to develop, making it possible for fierce competition to occur.
Real Madrid are still favorites, but I don't think it will be easy for them.