Chelsea have seen steady improvement since Maresca's arrival, and their success in winning the Club World Cup should be a good indicator that they can do the same in next season's Champions League.
You're right, as you said, Chelsea shouldn't be underestimated. Personally, I'm quite confident in Chelsea, and they deserve to be placed among the favorites to win next season's Champions League. If that happens, it wouldn't be a surprise, as Chelsea have a pretty strong squad right now.
Maresca’s influence since joining the club has been immense, I must commend his leadership abilities and the club that have put in effort to provide a good atmosphere and a great and talented squad for him to work with. Indeed this has strengthened the team and made them strong enough to be able to compete at all levels next season, I have said this many times to look out for Chelsea next season because they are the team to surprise us.