Guaranteed 1/8 finals and then how lucky they will be with the draw. With the new format, I don't think Bayer will have problems finishing in the top half of the group. If the competition were held in the old format, then reaching the 1/8 would also be guaranteed since Bayer, as the German champion, would be in the first pot and the likelihood that a group would turn out like Group F this season is very small.
Many predict that Bayer Leverkusen will be the center of attention in the next Champions League and want to see how Xabi Alonso competes with many outstanding coaches who have experience in the Champions League, but we cannot guarantee to what extent Leverkusen can survive in the Champions League despite the previous unbeaten achievements, it is possible but it may not be what we imagine or go the other way and cannot survive even in the group qualification.
But it is interesting how far Xabi Alonso will take Bayer Leverkusen, whether it will reach the final like Dortmund or not.
It seems to me that the Swiss system (which will be used next season) favors the favorites. If in the old format you lost to an outsider/strong opponent, then you literally had one chance to correct the mistake (in the return game in which the opponent could choose a reliable bus option). In the new format, the more you lose, the easier the opponent you get next time. I have little faith that any of the favorites will lose several games to outsiders and not make it to the playoffs.