This is great!! Wonderful job! There are a few things I'd add though (spoilers!):
- Upgrading the whistle actually increases the speed of the warping cutscene, particularly when holding the jump button down to cycle through locations. Your mileage may vary in terms of usefulness, but that's what it does!
- You can access the warp to HIDDEN VILLAGE early (even before going to meet Death for the first time/using the LIGHTHOUSE warp) by falling down from CRAGGY NOOK on the mountain onto the trees below. Platforming across them will get you to PRECARIOUS without blue herbs, or any additional items at all, for that matter!
- The ice wall in GREAT ICEBERG can be melted with a lava golem from Hymnir Volcano as well as with bombs! It's harder, and probably not something anyone would willingly try, but it works!
- Speaking of Hymnir, the fast-travel point in Hymnir can be reached early (without doing the loop around) if you can jump up to the ledge. See your tips and tricks for some ideas about how to do that...
- In The Creature, on the north (wand-centric) path to GAOL, you write, "In this room, shrink down using the lens
for a floatier jump and make a tricky jump around the corner using the boots to lend on the cloud." There's actually a slightly easier way through this room; if you return to the previous room, do the trick with the falling pot/respawning again to return to the doorway, and go back to the room with the cloud/pit, you can levitate the pot, throw it over the pit, and use it as a platform to reach the cloud. It's finicky, but doable, and perhaps easier than going around the corner with the lens/boots.
Also, I'm sorry about the 51 gems thing! No clue why that happened... I will investigate if/when I have time.