Okay, you've watched and have been recommended quite a few, so I can't offer much. But, while I'm here:
Clannad (someone mentioned Canon, so I HAD to mention this one) and Clannad After Story. If can make it through the first season, you can make to AS. Clannad After Story is amazing, but UNBELIEVABLY HEART-WRENCHINGLY SAD.
Jamescoker mentioned FMA, so I'll elaborate. If want a darker adaptation go with the 2003 version. If want a (slightly) lighter version that is more faithful of an adaptation, go with FMAB (2011).
I also suggest:
-Zankyou no Terror (if you like terrorists)
-Black Lagoon (for an increase in testosterone)
-Ghost in the Shell Stand Alone Complex (1st +2nd season, if you want thought-provoking +action)
-Fate Zero + Fate Stay Night Unlimited Bladeworks (highly recommend 2014 version, with second season coming this spring season; also, fate zero is the prequel, but you can watch either or first. If you want a surprise, watch UB first, then FZ for backstory. If you're a chronological-freak like me, then FZ first.)
-And if you want some lighter stuff: Oreimo, Toradora and Sakurasou no Pet na Kanojo,.
(I could recommend a lot more, but these should keep you busy for a very long while...)