I'll be honest : 100% of these are slightly older.
Ghost in The Shell evartiem.
Angel Beats was...interesting.
Clannad seems like a harem, but compared to today's harem animes, this one uses a forefront of character interaction instead of plotless ecchi. You'll never want to watch any other harem anime after this.
If you're into plot twists that would confuse even a sailor, Tsubasa Resevoir Chronicles.
Sgt. Frog; so childish...yet...it's not.
Fullmetal Alchemist, if you haven't already.
Essentially, 90% new animes are tasteless harems to jack off to. If that's what you're seeing first thing in a synopsis, SKIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIP it. You'll be wasting your time (unless you're frustrated that way :P)
Examples TO SKIP
- Infinite Stratos (plot almost loses traction entirely for all of season 2; season 1 is just building the cast)
- 90% other harems. TRUST ME ON THIS BRUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU...UUUUUUUUUUUUUUUUUUUUUH...
?Others from other people :
Parasyte, as it isn't dark, but not too dark as the story progresses.
Ronja, the Robber's Daughter, because it's Ghibli's first TV series.
SAO with your own opinion...and maybe read the light novel for a clearer self-interpretation.
If you're into slice-of-life comedy (romance as newlyweds included) : Danna Ga Nani O Itteiru Ka Wakaranai Ken
Daily Lives of High School Boys : you'll be WTFing all the way.
Black Lagoon; fun to see an anime where everyone's a "bad guy", and the one guy who thinks he's above them all descends so far down...
Code Geass (the original series); staple anime if you're into a story that runs like an RP with mechs.
I'm out of ideas.