Dark floors show dust, dirt, specks of everything, so it is harder to keep them looking clean.

It can be. Using a satin finish over the floor will go a long way in helping to hide dust and marks.

Lighting is an important consideration. Light floors reflect light making a room brighter . It is a good idea to do a lighting calculation as this may influence your decision. Is it a room with counter tops? Making the floor and counters contrast helps with aging in place and it also helps make the counters pop. In terms of dirt control, the quality of finish is at least as important as the color.