I played some more Minecraft today. I've explored a bunch more of the underground tunnels I found last time, but there's still more to go. They have a monster spawner every dozen blocks it feels like, so it takes a while to get through them. Though a large part is also just the sheer amount of loot I find, which means I have to run back to my house to dump everything I've found.
At one point I managed to accidentally fall into a pit filled with about a dozen mobs and immediately died. When I went back to get my stuff, I immediately fell into it again. Luckily for me the mobs had despawned when I died, so I was able to just grab my stuff and continue.
I now have two backpacks which I've just upgraded to double their size and I created another storage container that's fairly small, but can hold multiple stacks per slot. Hopefully next time I'll be able to clear the tunnels without running out of inventory space.
I was missing options on my chests to sort the items inside of them and to quickly deposit from my inventory to a chest, which are usually added by a mod in most modpacks, but I found out I just need to craft some upgrades to unlock these options. Which is a bit tedious, but not too bad.
On the other hand, this modpack includes a mod that allows you to mine an entire vein of ore at once, without having to craft anything specific, which saves a ton of time. And it's not just ore, you can destroy any chunk of the same type of block at once, so it works great for chopping down trees as well. I think you can even set a shape to mine out, so you can mine out hallways much faster for example.