I just read that this is the first game you guys made so congratulations! I hope you had a great time doing it, doing jams like this is a great way to learn a lot by doing from my experience so keep it coming.
I could not finish the game, i got stucked the two times i played it in different places, first i fell through infinity and second i got stuck between some green blocks.
The best advice i can give you is to try to complete the experience you want to give players. For a first jam, first game, this entry is totally awesome but keep in mind that making something from start to finish is a huge of a challange here, even if its only one single mechanic and a really short game.
This project at first seems ambitious for its worldbuilding (even for experienced team i think), the place has to be huge to work out with the exploration and that leads to many assets and create cool spaces the player can go and dont feel monotone. Maybe next time, smaller better separated places, or maybe add more challange to move around (like obstacles or enemies) so the game dont focus only in exploration. Or try a smaller scope, try to think of the most simple game and try to make it to the end, there is a lot of learning there for sure in the polish and details.
Also there seems to be some debugging information and two playable characters for some reason, at first confused me a lot, i assume not intended.
The music was indeed wonderful so good job there, also the art i felt was nice seeing those screenshots in the game, but could not felt the same playing it.
Good job guys and congratulations for your first game! Thats the way to start, hope you can take something from my feedback, good luck!