I'm pretty actively engaged in current series and though I haven't seen all of them, here are some rankings. Completely my opinion.
  1. 1.
    Assassination Classroom
    The concept is brilliant and hard to explain, the animation beautifully lined and still very dimensional. The characters are ones you really care about, and despite the weirdness, you end up very engaged in the teacher student story. Ass Class is ongoing and probably the best of the season.
  2. 2.
    Kekkai Sensen (Blood Blockade Battlefront)
    Though the concept of alterworld aliens mixing with vampires and werewolves sounds like it was written by a 12-year-old, the story ends up interesting by the seventh episode. Oddly objective at times, the quick scene shifts take a little getting used to. It's hard to care at first, but the ending is so cute!! Currently running.
  3. 3.
    Gatchaman: Crowds
    An all time favorite series of mine set in 2015 that completely accepts openly gay half alien men and crossdressing. Features my very favorite anime alien, Berg Katze. Though the series is technically a reboot of the '70s Science Ninja Team, which I love, the 12 episodes and directors cut 13 stand strongly on their own. Aired in 2013 with a new season this July, so now is the time to watch.
  4. 4.
    Durarara!! and Durarara!! x2
    A love story that aired originally in 2010 and had half of a second season this January. The gangs and spirits of Ikeburkuro really make the show worth watching whenever. Absolutely beautiful. If you haven't seen it, spring is the time to catch up. Durarara!! x2 ended halfway on a cliffhanger and picks back up in July as well.
  5. 5.
    Seraph of the End (Owari no Seraph)
    I'd like to call it a love story between Yuu and Mi(kaela) but that's a little heartbreaking. This week on anime kids who did nothing wrong in a near dystopian vampire story set in an overgrown Tokyo I wish I didn't know so well. The animation is okay and the story formulaic, but damn, I just want Yuuchiro and Mika to kiss already. Currently running.