After a while of playing through the game again, I just thought of a few more new ideas I'd like to share with you if you'd want to add any of them in.

Obsidian horseshoe, Magma Skull, Obsidian Skull Rose, Molten Skull Rose: Grant the wearer 2 defense. The obsidian shield would also gain an additional 2 defense, granting the player 3 defense now. (I made comment suggesting this earlier as a single idea, but I decided to delete it and just add this idea onto this list instead.)

Frozen Tortoise Shell: Grants the player 4 defense.

All of the glowing fishing bobber variants: Grant the player the sonar potion effect while fishing.

Guide to Plant Fiber Cordage: Increases alchemy plant collection (similar to Staff of regrowth).

Tabi and Ninja gear: Increases movement speed and jump speed by 5%.

Royal Gel: Increases the spawn rate of slimes, and slime have a higher chance of spawning as treasure slimes (slimes that have items inside of them).

Worm scarf: Grants the wearer 10% increased damage, but ONLY when they are currently at full HP.

Gravity Globe: Grant the wearer immunity to fall damage and the distorted debuff, Greatly increases the wearers movement speed, jump speed, and jump height, and grants the wearer a 20% damage boost when they are currently in reversed gravity.

And that is it for my new ideas! Let me know what you think of them.