I think y'all have a really solid foundation for a game here! I like the mechanic of having to think on the fly when my character switches, and how that introduces a whole bunch of tactical considerations.
There are few things I would urge you to do when you go about polishing this bad boy:
- Have some kind of audio/visual indicator of when the player character is going to switch (you could have a diegetic reason for this too: dimension switching, quantum entaglement, nanobots -- go wild)! The upshot is that I had some deaths that felt unfair because my character switched without warning.
- Consider included a health bar. Doesn't have to be fancy, could even just be giving players 3 Hits before they die.
- Add a death animation! As it stands, death feels very abrupt and jarring. It doesn't have to be an overwrought thing -- even just a simple explosion with the "RESTART or EXIT" menu fading in would really make the experience smoother. Hotline Miami nails this kind of thing
- More levels! Reward skillful play with more stuff to do and places to see!
Considering the time constraint, y'all did a great job! Well done!