Experimenting with the lighting helped me realize how much it can affect the mood. A sunny day is usually bright and cheery, dusk and dawn are beautiful, and night time can harbor just about any connotation: serenity, horror, or simple emptiness.
Lumen is revolutionary, and impressively so. The alternatives are not just slower, but more energy-expensive, as well as being much more rigid in their usage. Lumen fits any situation like gas in a balloon: it can expand to meet the needs of the balloon, or it can contract itself and stay smaller.
I don't even know what would happen if I didn't have the correct gamemode. I suppose the player would stay as a camera. I tested out another gamemode, paper player, and it locked the camera in place. That seems just as disastrous to the experience. Keeping the levels in their correct gamemodes is important for making a game playable.