If you can see the metering read-out, the dots in + or - direction are clues to what the current settings will achieve.
The drawbacks with having an EVF adjusted to show a bright view, no matter what your exposure settings are, would be a tendency to blind the eyes if it's very dark, and some situations can give bad and visible noise in the finder. The latter in fact often occur when one shoots in UV and uses efficient UV bandpass filters.
