Air, Saishuu Heiki Kanojo Recommendations
Both are incredibly sad anime, and i could go into further detail of how they are somewhat similar, but it would have to include spoilers, so lets leave it as that.
At first glance Saikano and Air do not seem to be very alike, the first having a post apocalyptic setting and a plot that focuses heavily on war while the second takes place in a peaceful village for the most part, yet they are soul mates in how they handle a sheer dose of tragedy that dominates the later part of these series. The slice of life moments, heart felt romance, cute character designs mingled with nostalgia are more arguments that establish Saikano and Air as epics of sadness.
Both shows are like an emotional rollercoaster from start to finish, and both are equally heart-wrenching. In a good way.
Both series have a core love story that has difficulties along the way, multiple love interests, and a strong tragic element. Saikano's heavy on the violence as well, but otherwise they're quite similar thematically.