I also love the art, it was done by Thanos Gramosis, Very lucky to have him on the team :)
The gameplay was my job though! I spent some time on the movement to make it feel ‘birdlike’. I did do some testing with other people, and made the movement more fast-paced as a result, but maybe it ended up not quite being fast or slow enough to feel ‘right’.
Your comments on checkpoints is interesting, as I did consider them at the beginning. I never really considered how I should take into account that in a game jam you want others to experience everything without frustrating them, that the level of investment is much lower than a ‘proper’ game. I will definitely remember that for next time I do a jam, thank you!