I'm definitely in the minority here, but I think this anime is quite overrated... The story is decent, but (like things that deal with time travel) not everything makes too much sense.... I can't say I really like any of the characters in particular.... the art style is not bad, but not something that stood out to me...
It was definitely interesting and it is worth rewatching so you can understand what's going on.... but I would definitely NOT put this as the 2nd top anime right now...
Perhaps my review score is low because I want to offset the hype, but I don't feel I'm too off base... But that's just my opinion.