It has caused for me a couple changes in how I play, but that doesn't mean if I have had to change that it is bad. In general a game that remains stagnant without changes, updates, and new content will also lose players. Have I stumbled around in dark dungeons? Yes, sometimes even ones I thought I knew. Did I continue to stumble? No, next time I go back I remember (hopefully

) where I turned wrong so it stops being an issue. I have had to rely upon the mini map more to see mobs forming and other players approaching. Is it perfect? No, sometimes stuff happens quicker than I anticipated. But next time I am more careful to watch. Do I fish and mine more when darkness comes? Yes, but now more interesting items can be fished, and mining is always a dull thing to do or crafting or cutting trees so nighttime gives me a perfect time to do that. Again it was an adjustment but not where I could not find a useful way to spend the time. So I have adjusted. Would I rather have light all the time like the first 2 1/2-3 years of playing? Probably yes but that's more because I am a creature of habit and resistant to change. (unless of course it's a change in my favor that I really like

) We can be so fickle sometimes. I can oh and ah how beautiful the glowing crystals look in the dungeons under Silverwood but be grouchy about the mages under kings garden who come out of the darkness in twos trying to zap you!
I do however have concerns for the players who only have a small amount of time to play. If the only time they can play is during the darkness periods that would indeed be discouraging to not have access to full light very often. New players I think will see the night as a given and part of how the game works.