I nominate Planetes, Pluto and mostly Kiseijuu for the best Sci-Fi Award.
Planetes as a series about learning to accept compromises in life belongs to best debut works I have ever read. Pluto is compact and fresh recreation of Tezuka's story about Tetsuwan Atom and The Strongest Robot on Earth. It doesn't suffer from random "one-shot" stories and unnecessary prolonging like Urasawa's other works. My main nomination, Kiseijuu by Iwaaki Hitoshi, created quite a craze in its time. People loved it, literary critics loved it, academics loved it, it sold incredibly well and it placed quite highly in some literary masterpieces rankings in Japan etcetera. This is all nice but in the end it's the actual work what matters. Iwaaki (as usually) worked most of the time alone on the Kiseijuu - story and art-wise. In that sense, Kiseijuu really is "his work". Iwaaki told a story about a regular boy, Izumi Shinichi, who gets into very bizarre situation where his right arm is devoured and replaced by a parasite. Story of Shinichi is full of bizarre happenings, drama, confusion and death but also humour and compassion. Iwaaki's masterful storytelling is completely aware of the silliness of the story and strikes the perfect balance between drama and "calmness".