I get it daytime helps out players in building, however a lot of the art and the lobby itself takes place at night. It'd be better if there was a day-night cycle in sandbox and some levels would take place at night and then day and then over again, you know what i mean.
A side idea is one i pitched in normal chat but Night Time would make for some good 'Intermission Levels' where the Inventors Club can scavenge around the park at night with flashlights, grabbing items and avoiding the neighbor and his creations. It would be a great break from the game play and will be rewarding players for exploring like what the loading screen says.