You should finish Code Geass and Gurren Lagann for sure, they are awesome.
I'd also recommend Sengoku Basara, if you like action/fighting types.
And D.Gray Man is good if you like your action with a serving of the supernatural/fantasy stuff.
I actually recently watched Ao no Exorcist and enjoyed it wayyy more than I thought I could enjoy a sort of school-based setting. I cried at least three times in the series and I found a lot of the relationships really moving.
Watch Last Exile. I liked Noir because it had female heroines that weren't just T&A, but in depth characters. Also the music is FANTASTIC.
ive liked some anime that FUNimation picked up like Darker than Black and Blassreiter
you can find a lot of animes from them to watch, but they arent all free anymore and have a couple ads
every anime i've watched in the past year and a half :
great anime:
Nichijou Pani Poni Dash Trigun Gunslinger Girl Basilisk Galaxy Angel (the original series)
Shigurui Nerima Daikon Brothers Rurouni Kenshin
good anime:
Soul Eater
Kyo Kara Maoh (it stopped getting dubbed into Enlgish about halfway through but you can find the rest subbed online)
Claymore
Gilgamesh
Mahoromatic
Cowboy Bebop
Samurai Champloo
Gurren Lagann
Naruto (some of it, the fillers suck)
Noir
Air Gear (ended too soon, try the manga as well)
Speed Grapher
Strawberry Marshmellow
overrated/probably should avoid (or at least i think it's pretty overrated/not as good as most other anime out there): Melancholy of Haruhi Suzimiya Karin Lucky Star Ouran Mawaru Penguindrum Spiral Jing: King of Bandits (liked the manga better)
Chobits Here is Greenwood Loveless
Death Note
i guess it really depends though if you prefer Type A or Type B anime, gag comedy or a straight plotline, shoujo/josei or shounen/seinen etc.
* i reorganized the list so it's easier
** i made the font small because the list is kinda long