I have shot with color slides, so that is maybe more critical.

In the past I have bracketed for research.

I find that if you are in dusk, not black. I tend to meter somewhere grey, this might be side of a concrete building with traffic lights, I then overexpose 2 stops to what the meter says. If for example you are photographing a water fountain with bright lights like buildings, car streaks, city lights use 2 again. While some highlights will blow out, in night photog, it's gonna blow anyway and to me it looks more natural.

If I just use 1 stop, the dark areas is too dark.

If on the other hand, I am photographing a park for example. I might meter onto grey area and overexpose 1 stop. This looks darker but it is more natural b/c it doesn't have all those extra lighting ....