Me too I hate the fishing in stardew valley and suck at the game, I managed 5 fish while a friend managed 31
the initial idea was to make something a kind of life of pi where you would be stuck on a boat with a tiger and would have to avoid the tiger while keeping you fed and warm,
but since we lost the first day working on a game that ended up in a corner where it didn't really stuck to the theme and would have been hard to design puzzle for,
the idea devolved into a simpler 1 axis one button game where you need to keep fishing to survive while avoiding the bird (which was supposed to dash at you but due to time reason drops bomb)
I am planning on polishing it up, remaking the boat and fisherman which is half the resolution of the other assets, make mechanic more obvious and introduce a real difficulty curve (maybe put mechanics that didn't made the cut like Morse code typing and weather which change the force pushing against the player)
introducing the mechanic slowly to the player is a most, I like the way you did it with your game
the bar is splited in half since the heal upgrade restore half of your life bar (30 second of a minute)