I now know that I can submit before it's finished, lol. This was my first ever game jam, so it was very much a learning experience.
I completely agree that the introduction is very exposition heavy, and feels very heavy-handed. I'll check out the GDC talk, thanks for sharing and for the feedback!
Also on the second level there was supposed to be another character that would guide you to the walrus (and then the walrus was going to give you a quest to fetch something from the orca filled region in the southwest of the map) but I ran out of time. If you wanted to play it to the end, there's a little passage at the far right of the second level that you can swim through to to get to the very northeast corner of the map, that's where the Walrus is. Speaking to him will clear an oil-spill blocker for another passage on the left side of the map, which will take you to the end of the game.