If you want something light hearted and feel good, aria the animation is one of three, the animation, the natural and the origination. It's about venice on mars, and the main character wishing to be a undine, (a master female gondolier. The music is so good, the characters, the world building. The show was so amazing, and still is to me, that many times I've wished that upon death I could be born in this utopian world. I have never found a slice of life like it despite searching for many years.
If you want horror, I really loved shiki, another, and jigoku shoujo, (hell girl).
Shiki is about vampires that kill villagers in a remote town, sometimes causing them to come back like them. It constantly questions morality and examines this through the vampires and the surviving villagers, who is the monster, who deserves to survive.
Another is basically a final destination show, but in anime form, and it is very enjoyable. Lot's of deaths and mystery throughout the show.
Hell girl is about a site where you can request the help of a servant of hell and in exchange for your soul you can instantly send your hated target down immediately to hell, (usually includes a wondrous trippy torture ride before the victim gets their just desserts).
If you want philosophical, one of my favorites is haibane renmei.
Haibane renmei is essentially about a girl who committed suicide and ends up in purgatory, it being a town with large walls, that she and the other winged, deceased live in. They aren't allowed to cross the wall until the day of flight comes, essentially allowing them to pass on from this state.
Ill finish up with a space epic from the 80s known as legend of the galatic heroes.
Though it has a total of 110 episodes, it is a amazing story of philosophy, strategy, politics, and more, the story being told from the perspectives of reinhard of the empire, and yang wenli of the alliance. The fights in the show take second stage to the first hand strategy of the commanders who fight them, the politics of both democratic, and the dictatorship showcasing good and bad, (for example theres a scene where a space ship explodes, showing the dying soldiers, one of which is caught on fire, and burns away while grasping a locket with his family, his motivations, and a burning picture of the leader of earth smiling, (what he died for). Normally I can't stand shows with episodes of this length because they lose themselves in the run time, but this show pulls it off spectacularly. Would recommend!