Very fun little survival game! I liked how the Grey kept a constant pressure on, and while the player could scare him off for a while he'd always come back. I also especially liked the hook mechanic, it felt polished & satisfying.
I think what it needs most is some element of personality, a narrative or "human" element for the player to relate to / connect with. My mind went to something like the Radio in Subnautica and the whole Aurora sequence (I won't say more in case of spoilers, it's an excellent game tho I highly recommend). But maybe you could do something similar where you start the game with a handheld radio, and you receive a transmission from someone saying they'll come rescue you, but before they can find you you'll need to build a beacon.
That gives brief exposition, and also introduces a new character. You use that to build more "uplifting" vibes by tying more story into that character, maybe they contact you each night as the sun sets, reassuring you that they'll find you, asking you about your life, what you'll be going home to after rescue, etc. Something to tug the heartstrings.