It's great to read feedback from an astute player. Indeed, one of the aims was to give the player more agency and control over their progression.
I hear you regarding the possibility of the hero getting 'lost'. I stuck to whole number scaling since the assets were pixel art. So if I were to double the player sprite size, it would get too big. If I were to halve the size of the UI elements like the countdown timer, it would've gotten too small given its importance. Still, it's a good point and I will probably be less strict about integer scaling of sprites if/when I make my second game.
Thanks for your time playing, reviewing and sharing your feedback :)