If hte game seems to dark you might need to adjust the gamma setting on your driver. This is a different setting than brightness and should probably be the first one you try adjusting.

I had the same issue with the view in game being almost completely black at night, even with a torch it was like walking in a black fog. After i tweaked the gamma a little it improved significantly. There was a thread awhile back requesting an in game gamma setting for just this reason. Seems that on some installs the game is just too dark at times.

As to the day not being long enough I have to dissagree, 21 minutes is a reasonable amount of time, with the 9 minut night it make a "day" a tidy 30 minutes IRL. And it's also plenty of time to get enough resources to craft a hammer and axe then build a basic shelter with a bed and fire.

This is of course just my opinion based on being used to a 21 minute day, First survival game I ever played was Mincraft which had a 20 minute day, though MC also had a 20 minute might. if your used to games having longer days I can understand it might be bothersome