Genuinely a masterclass of good game design. A few of the bigger notes I took:
- The upgrades preemptively counter what the player could perceive as "frustration" or "tedium" towards the end game. I.e. when the player is tracking down the last few rare fossils, the upgrades they've purchased over the whole game make getting those specific fossils easier via more bag space, double-drops, increased rarity, and QOL boosts like faster move and dig speed. REALLY good design choices there.
- Really appreciated how the collection log lists what weather your missing fossils are available in, so once I had all the fog fossils collected, I knew I could head back once I got my bag full for upgrade points (instead of checking every drop on that level hoping for a rare that wasn't possible to drop).
- The perfect pack bonus was *chefs kiss*, perfect. Not so OP that it was unbalanced, but enough of a benefit that it naturally encourages the player to interact even more indepth with the bag sorting puzzle mechanic. Again, great design choice.
Other misc observations I had, really nice use of the color palette in your art. You managed to look unique and distinct even from the other games using the same palette, which takes skill. And while the number of controls looked a bit intimidating just reading from the description, once in-game they're perfectly intuitive. I did run into a few little momentary freezes & audio stutters on the performance side, but we're working with web builds so that's pretty expected.
Overall, really well done!