use auto first, if you don't like it, than adjust the white balance.
There is no right or wrong, it up to individual.
there is no correct white balance to use for nigh cityscape scene.
I use Kelvin, Tungsten, Fluorescent, or Daylight depends on the time of the shots and the mood I want to create.
With regards to the pics above.. I would like to ask, for long exposures like the pictures above.. Given same location but if i am using d90+tamron17-55mm i am shooting same composition.. I use f/16, shutter:30secs, isoL1.0, wB: tungsten and clouds.. To get crisp and sharp pics shud i stick to f/16, 30secs or f/11,30secs, which settings is better f/16,13,11 or 18? Shutter: 30s, 25s, or bulb? Thanks
With regards to the pics above.. I would like to ask, for long exposures like the pictures above.. Given same location but if i am using d90+tamron17-55mm i am shooting same composition.. I use f/16, shutter:30secs, isoL1.0, wB: tungsten and clouds.. To get crisp and sharp pics shud i stick to f/16, 30secs or f/11,30secs, which settings is better f/16,13,11 or 18? Shutter: 30s, 25s, or bulb? Thanks