I love the dark vision feature in this game and how it is implemented and how it works, however,
All races should be on par with each other. There are many dark places in this game where the races without "Dark vision" are gimped with a significantly lesser chance to hit. This will be a major factor in picking races, people will not play races that they would normally would want to play because they don't want their hit chance to be so reduced.
How does that work? If all races are on par then there is no dark vision to begin with.
Torches, Wizards, Clerics...many things provide light. Some of them seem to not work however so maybe they should start by fixing the light sources to actually negate the darkness penalties.