I made a small pixel idle aquarium game and I'd love your feedback

Tiny Tank Tycoon is a relaxing idle/clicker. You tap to feed your fish, collect 12 species (guppies up to a tiny whale), buy upgrades, pop treasure bubbles, and rebirth your reef for pearls. There's a day/night cycle, tank themes, and 20 trophies. It's free in your browser: https://wortelke.itch.io/tiny-tank-tycoon What would you want to see added? I'm planning updates based on what people say.

I already made one update;

New in the update

• Random events (about every 2 to 3 minutes, lasting around 45 seconds):
  • Cold Snap: it tints the tank icy blue with falling snow, slows the fish, and cuts income by 40%, but taps pay triple.
  • Plankton Bloom: a green tint and +50% income.
  • Golden Tide: golden fish show up much more often.
• Mutations: every fish you buy has a 2% chance to mutate, and fish can also mutate by themselves over time. Mutants glow in new colours and earn 4x income. The shop shows how many of each species are mutants.
• Limited fish: a new Rare tab. Every few minutes, a Golden Koi, Ghost Angelfish or Crystal Seahorse is for sale for about two minutes. Each adds a permanent income bonus (+20%, +35% and +60%), only three of each can ever exist, and they keep their value across rebirths.
• Two new upgrades: the Aquarium Heater reduces cold snap damage, and the Mutation Lab raises mutation chance.
• Five new trophies, 25 in total.
• Cap: Golden Net stops at level 5 and then shows MAX, and buying "Max" can't push it past that.
• Effect per level: golden fish now come 7% sooner and pay 5% more per level, down from 10% each.
• Old saves: a save with a higher level (I tried 9) still loads and counts as level 5.
• Golden Tide event: it speeds up golden fish by 2x, not 6x.
• Minimum gap: there's always at least 30 seconds between golden fish.

Golden fish: the payout is now 20 seconds of income, down from 60. I kept the spawn timing as it is. Catching every golden fish now adds about +30% income with no upgrades, and about +50% with Golden Net at level 5. 

Rebirth cutscene:

1. The screen dims, black bars slide in, and the words "The reef swims on..." appear. Every fish speeds off the left or right edge of the tank.
2. The tank is empty and a glowing pearl rises from the sand, and a counter counts up your pearls and shows "Reborn!".
3. A white flash fades out and the new tank begins.

Taps and shop buttons are blocked during the cutscene, and income pauses so nothing odd happens mid-scene. If you own limited fish, they swim back in from the edges afterwards.

Other animations:

• Newly bought fish pop in with a small bubble burst.
• Mutations and limited fish arrive with a burst of sparkles.

Rebirth cutscene sounds

• Fish swimming away: a low descending whoosh and a rising water swish, with small bubble blips while they leave. The background music dips so the scene stands out.
• Pearl appears: a soft shimmering chord, a rising sparkle run and a low thump, with a quick tick for every pearl that counts up.
• "Reborn!": a short bright chord.
• White flash: a rising sweep, then the music fades back in.

Sounds elsewhere in the game

• Events: Cold Snap gets a windy rumble, Plankton Bloom gets bubbles, and Golden Tide gets a bright sparkle.
• Mutations: a sparkle burst.
• Bubbles and new fish: a pop for treasure bubbles, and a small blip when a new fish appears.

Two small fixes along the way:

• Several achievements unlocking at once used to stack their chimes into a loud blast, so they now play at most one chime every 0.4 seconds.
• Buying lots of fish at once now makes one blip, not one per fish.

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