Wow, it sounds like you really explored the game fully! I didn't expect anybody to find or notice all that stuff I snuck in.
I have something like a "Sticker Book" in mind for the full game! I think two big things missing to make this a full game are 1) a longer series of trials to advance through, and 2) a sense of progress where you can show off how much you've played, your best times, your best scores, which frogs you found, and things like that.
I have some ideas for how to fix each of those! And based on your sticker book idea it sounds like maybe you have some ideas too. But mostly, I'm thinking about a series of many, many worlds which each introduce 2-3 new puzzles at a time, and which intermix those puzzles with ones the player's already seen (like a 50/50 mix of old and new stuff.) And, some little things like the sticker book idea where the player can relax and look at all the cool stuff they did.
If you have any other ideas I'd love to hear them! Thanks so much for playing frog finder. And good job on finding so many frogs 🐸