If you're interested in Mechs and shonen style story and characters I highly recommend Gurren Lagann

Outlaw Star is also really good

'Attack On Titan' and 'Mahou Shoujo Madoka Magica' are my two most recommended animes. 

If you enjoyed Cowboy Bebop I think you would like Eden of the East a lot. It's short and sweet and has two films as well. (I dunno how I drew that conclusion, I just think you would like it). It's pretty serious. FLCL is good too.

Baka and Test is a cute sort of high-school anime with a lot of good humour.

Eureka 7 and Neon Genesis Evangelion are good mechas. Fantastic, even.

Bokurano: Ours is a mecha, but it's in a class of its own. It's really tragic and thoughtful, and I think you'd like it a lot. <3

And of course, death game animes are always worth it (best genre 5evr); Deadman Wonderland and Btooom! are both good. c:

'Mahou Shoujo Madoka Magica'

This.

Watch Puella Magi Madoka Magica. You won't regret a thing. It's the most popular anime at the moment on the forums for a reason.

Death Note

Fullmetal Alchemist

Fullmetal Alchemist Brotherhood

Attack on Titan

Sword Art Online

Eden of the East

Rin: Daughters of Mnemosyne

Watch Madoka Magica as soon as you can. It's kind of incredible

Also Megas75 made a good recommendation up there. Gurren Lagann is a super fun show

i don't watch manga much, but I read it. One of the best manga/animes i've ever read was remote. Its a detective story that gets even more interesting with the detective's issues.

Something was here. Something was here. Something was here. 

Kill la kill.

A chaotically and fun over the top anime for anyone who's up for anime in general.

I see you've already seen Yu Yu Hakusho...

Watch it again.