It's no longer about who is big and who is not. In fact, last season should have taught most people a lesson. For example, how many people here thought that PSG would go all the way and lift it? I am quite sure they were very few, if not, none! If you recall very well, PSG had to even go for play-off in order to qualify for the next round.
Strength or Player quality aren't always the key to a club's success, and I agree that last season, very few people believed PSG could achieve new Champions League history, but that was achieved through their hard work. It's too early to say which club is strong and which club is weak, because sometimes our predictions don't go as expected. This can be seen more clearly, so the round of 16 could be the first step to see how far the teams will go in this season's Champions League.