Out of 8 matches there are 3 matches that make me doubt and you need to reconsider. And I am not sure if someone else has answered but I will tell you about my assumptions, but this is not advice.
For PSV vs Arsenal you have great confidence in Arsenal but maybe you forget something important that some of Arsenal mainstay players will be absent due to injury. Bukayo Saka, Gabriel Jesus, Gabriel Martinelli and Kai Havertz. While the last appearance in the EPL against West Ham, Arsenal suffered a defeat. Do you still believe that victory will be on Arsenal side?
For Madrid's performance, I would not believe Madrid would lose. Madrid has more experience and the worst result is just a draw. And losing seems impossible to me.
Next up for Aston Villa. Take the H2H stats into account and it could be a big problem for Villa. Club Brugge are not a weak team and they can be a tough opponent at home. A draw could happen.
Actually, Arsenal's performance cannot be predicted accurately by their way of playing because sometimes they appear impressive and can also lose their best form until they lose. However, in the Champions League they must focus well even though they are not strengthened by some of their core players, they have to fight to win the first leg or not lose.
For me, Arsenal's performance this season is also unstable, they also lost a lot of points in the domestic league, even in today's match where Arteta's troops drew against Nottingham Forest. So one of the factors that they will lose the opportunity to compete strongly, so they must focus more on the Champions League if they are unable to compete in the domestic league.