I just watched hunter x hunter and it took me 3 days, lol i spent 10 hours watching it straight it was amazing. I have watched
deathnote,
fma brotherhood,
champloo,afro,
kaiji,
akagi
spice and wolf,
guilty crown
haruhi suzumiya
code geass
dbz
kimi ni todoke
kaichou maid wa sama
one outs

so i prefer some anime thats not childish and reallly good story line like hunter x hunter and champloo

Gungrave

Mushishi
Soul eater was decent but you might think its kinda childish

consider using the Recommendation And Request Thread next time

baccano
cowboy bebop
yu yu hakusho
trapeze

Original Fullmetal alchemist is awesome.

Id recommend

To aru majutsu no index
To aru kagaku no railgun
Darker than black
Fate zero / fate stay night
Steins gate
Shingeki no kyoujin

And since you liked kaichou wa maid sama
Skip beat
Ouran host club