Overall, the content is really high quality, and I'm enjoying it a lot. There are just a few things I'd like to see improved.
1. Loot and exploration
The loot in the Guttering Hollow and Deepworks dungeon chests is honestly pretty disappointing. It's mostly just arrows and scraps, which doesn't really encourage exploration.
for exemple add crafting recipes to these loot pools, especially Goblin gadget recipes. Finding these recipes in dungeons could unlock the ability to craft those gadgets, making exploration much more rewarding.
Another idea would be to have a small chance of finding an actual gadget in a chest (e.g. a 2% chance to find Rocket Boots).
Just throwing an idea out there, but I think adding rare loot like this would give players that little dopamine rush every time they open a chest, thinking "Maybe this time...". It would also give players a reason to revisit Guttering Hollow whenever they find a breach.
2. Void Bear spawning
Unpopular opinion, and not a major issue, but I'm not a big fan of having to use a spyglass to find the Void Bear. It makes things more complicated and forces you to craft an item that I'm personally not that interested in using, although I'd be fine with the spyglass being obtainable as chest loot.
I think the Void Bear event should spawn randomly without requiring a spyglass, while keeping the current Void Heart system.
3. Hardcore Gobliterator reward
I also think it's a shame that there's no extra reward for defeating the Gobliterator on Hardmode. It would be great to get at least a decorative trophy to display in your base.
It would give players something tangible to show off their achievement and provide an extra incentive for the bravest players to take on the challenge.