hopeful, wistful, and enchanted
A player is immersed in green spaces. Either players must interact with greenery (e.g. exotic plants, dense brush) or the setting is vividly in a green space (abandoned greenhouse, deep forest).
Spiritual guides might give a more fantastical feel to the game. Maybe these are very subtly fantastical characters that a player must seek guidance from to advance in the game. The clues may lead to the guide and the guide may be the last interaction in the game.
Minimal text adventure. Maybe the player does not have a lot of guidance and there are only a few words and phrases that the player interacts with. How could we build a narrative without using too much text? I think that would be an interesting mechanic to explore.