Shinsekai yori, Sidonia no Kishi: Daikyuu Wakusei Seneki Recommendations
-Both anime occurs in a distant future dystopian societies. Both societes look pretty weird for 20-21th century humans.
-Both anime presents a high level of sci-fi element and "the details", and in both humanity are endangered by extinction.
-Both have specific, non-standard artwork.
-Sidonia no Kishi occurs in deepspace, while Shinsekai Yori occurs on Earth in distant future.
-Sidonia no Kishi have male lead who is clearly "The Main Protagonist"(Tanikaze), while Shinsekai Yori MC's have no clear lead, both Saki and Satoru have equal level personalities.
-Sidonia no Kishi features more battle scenes, while Shinsekai Yori have much less of it.