i liked your old nihon-go spit, but it was a bit plain (only white color and stuff)
i think your new one is better~ personally id like something with machi or street style to underline the street life aspect of your new site...but now that i look closer there already is alot of street culture in the other places.
the idea of the present background is good i think. some skyline view of the city...possibly at night with more lights maybe??
just giving general ideas, since i am just a noob~
edit: maybe something like soul somehow combined with city...soul of the city city soul?? tama + machi?? XD
...well, since you had vitality and life on your brainstorming sheet
edit2: background color...i think its some brown tone...with a bit of red maybe?? dunno personally id like some different color, but i cant think of a better color. again, just a opinion of a noob. dont have to change it, as its ok.