Added a whole bunch of visual effects. Some using Godot's WorldEnvironment node and others are shaders. Went for a CRT effect to give the game some texture and a slight retro vibe, which is very popular and well appreciated by gamers. I felt it needed a little more texture, so I added some noise created using Gimp's filters. On top of that, I turned on Godot's glow feature to give the game an ethereal, surreal, dreamy look.
This all helps create the right kind of atmosphere. It's not dark and gloomy like blatant horror games, so people don't get the wrong impression as I'm going for a more lighter vibe. It's more of a thriller than a scary game.
All in all, I'm happy with this as the final look of the game.