Looking at every team in the champion's league this season, the winner is going to be either Manchester city or Real Madrid because these are the two teams I still find best amongst others, I know there are other good tea s from other leagues but these two stands out and have always been, even their team currently have all the star players you can think of , that is why I believe strongly that between the both of them, one person will win the champions league.
That has been the definite view so far and it is very difficult to avoid the fact that these two teams have good squads to win the title. However, if these two teams find it very difficult to face their opponents then we have to lower these expectations.
The reason is that it is not impossible that other teams will not learn from the same mistakes. It will indeed be very difficult for them to be on par with Manchester City or Real Madrid, but what I mean here is what if another team gives an unexpected surprise, wouldn't that threaten their chances of making it to the final? I think there are things that we don't really know and of course the confidence in these two teams will not be as strong as our confidence in winning them and on the contrary they will remain wary of other teams even though they are favorites to win.
Indeed, what we can see with the naked eye is that Real Madrid and Man City are the two teams that are favorites to win the UCL next season. As you said, currently there are lots of new teams entering the UCL league, it is not impossible that they will provide a surprise that makes both teams fail. Moreover, next season's UCL league system has changed, of course with this new system the course of the UCL league competition will be different.
In my opinion, clubs in more competitive domestic leagues will experience more losses due to the large number of matches, because each club must have core and reserve players who have good quality. This is so they can rotate their players in each match. Not to mention, if someone is injured, the coach will definitely have a headache arranging the line-up of his players. So teams that are in leagues with less intense competition will benefit more. Maybe the French League and German League, for example PSG and Bayer Muchen, will be more profitable in terms of player fitness.