Pep is the best manager in the world bar none and there's nobody I'd rather have managing our club, hopefully for quite a few years longer.
Saying that, his style is not suited to winning the Champions League at all. I'm fairly confident we'll have managers after him who will come nowhere close to producing the same quality of football or league dominance as Pep but will easily have a better Champions League record. As Zidane proved, sometimes you don't need to be a tactical mastermind to win the CL as long as you have the right squad playing the right system.