[VivisQueen]

Drama > Slow drama (Kino's Journey)
Drama > Tragic/Sad drama (e.g. Grave of the Fireflies, Hanbun no Tsuki ga Noboru Sora)
Drama > War/Military drama (e.g. Grave of the Fireflies, maybe Pumpkin Scissors)
Drama > Romantic drama (e.g. Nana, Paradise Kiss, Ai Shite Night, Rec, Tokyo Marble Chocolate)
Drama > High-school drama
Drama > Musical drama (e.g. Nodame Cantabile, Beck, Piano no Mori, La Corda D'Oro)
Drama > Sports drama (e.g. Major, Ganbare! Kickers, Hikari no Densetsu, Attack No 1)
Romance > Romantic tragedy (e.g. Kimi Ga Nozomu Eien)
Romance > High-school romance
Romance > Historical romance (e.g. Victorian Romance Emma, Lady Georgie, Rose of Versailles)
Comedy > Spastic comedy (e.g. Detroit Metal City)
Sci-Fi > Dystopic sci-fi (e.g. Akira, Kaiba, Metropolis)
Sci-Fi > Mecha (same problem as Space Opera, but frankly, there are sub-genres that just don't have the parent name in the title - might just have to accept that?)
Sci-Fi > Environmental Sci-fi (e.g. Origin: Spirits of the Past)
Fantasy > Environmental Fantasy (e.g. Princess Mononoke, Laputa)
Thriller > Psychological thriller (e.g. Perfect Blue, Death Note, Kaiji)
Action > Samurai/Ninja action (e.g. Ninja Scroll, Samurai Champloo, Stranger Mukou Hadan)
Shoujo > Mahou Shoujo (e.g. Card Captor Sakura)