I tried racing once, lost, and gave up. The ball game was fun but again, just did it once (I won!) and preferred to explore. The fishing wasn't my cup of tea either. I explored the islands around the motorboat a little bit but I shied away from taking the boat as well since I could see the post coming up soon and didn't want to get tooo distracted... 😂

And aaah I'm so curious about the mines, too!! I kept wondering if I'd missed a quest where you get a light or something to figure out what blocks it? Definitely something I'd like to poke around more if I replay, secret passages are fun. Unlike you, I decided to buy the extra feathers I needed, haha, I was just stuck flying below the Peak otherwise (but ended up finding a bunch of treasure chests and coins doing that, so I had enough to buy these feathers in the end!)

I got a controller for the diagonal moving reason you mention. I was struggling way too much with that first climbing tutorial at the very start without it.