Hey!
Thank you very much for tacking the time to write such a long and detailed response.
I'll give the color wheel generator a try, I have been using "coolors" in the past but for this game I didn't find it useful. Very few colors work with the underwater theme. I had an attempt of adding some corals in the background made out of pentagons but then, the UI problems worried me too much and ended up leaving it aside =).
The idea of changing the outline of the enemies may work, but what I observed that what makes it harder to see the player is fact that the bullets are the same color as the center of the player. When things move rapidly my eyes keep focusing on the bullets instead of the player.
Its probably both the bullets and the enemies that have to many similarities to the player.
I am very glad you liked the updates! Yes the upgrades really need a description. The "heavy" upgrade makes it such that you no longer receive
knockback and move slower (there is another one that makes the bullets bounce it is called "bouncer").
The game could use a lot more work, after this game jam all prepare some notes with suggestions and things that need to be done but who knows when, or even if, I'll update the game again.
Would love to add a boss at the end tho =}...
Thank you again! Good luck your next game jams!
What was the saying... ah I remember "May the bubbles be with you!"