Indeed, a main menu and pause screen will be added fairly soon after the jam ends (25 days from now).
As the game stands right now, the current checkpoint placement is the right difficulty for me, but I realize that I'm not the best measure of how hard it should be (due to the fact that I made the game). How often do you think checkpoints should be placed?
On the point of score, I wasn't planning on adding a scoring system, but now that you mention it, I could see that working well to encourage a more methodical playstyle that the game doesn't currently serve very well. Thank you for this suggestion!
Weapon upgrade-wise, I plan on having the player learn abilities inbetween platforming stages. For example, I plan on adding the ability to howl, which will act as a ranged attack.
Thanks for your suggestions! If you haven't already, I would really appreciate a good rating on the jam page!