As you said, I agree. Ancelotti is a coach who has experience and has had a fantastic run in the Champions League mainly because he has won several titles. Meanwhile, Chelsea and a number of their new players are struggling to find their identity again after being slumped this season. The Champions League is difficult, so we can't be sure which team will win before playing.
We all agree that Real Madrid has a better situation to win UCL, they have a more experienced coach and a stronger squad. However, it is just a stats or theory. The result of the match can be surprising or very different from our prediction. 
At the moment, the Real Madrid team can be considered the most favorite team to win the Champions League title. The main reason for this is Benzema's full fitness and his return to form. Last season we saw a Madrid side that won the Champions League thanks to Benzema's performance. However, their match strategy was amazing. And if Benzema can continue with such consistency, Madrid has the best chance of winning the Champions League title this season as well. Even if they don't win the La Liga title, maybe Madrid will win the Champions League title.