Thanks so much for all of this info! You're almost certainly correct that I'm overthinking this (it's definitely a talent of mine). I had been leaning z2 on the NAS only because I'd heard that the resilvering process can be somewhat intensive on the drives, especially when they're larger, but I had also seen folks say that this was probably overkill for most home settings and so I'm glad someone with experience on it could chime in. I think my biggest takeaway from what you shared is that it sounds like keeping the file system baremetal and fiddling with it as little as possible is the strategy (vs. virtualizing it and running it out of one large Proxmox machine, for instance). And I think you're totally right on the LLMs being the real sticking point; I'd had no idea just how resource intensive they were not just to train but even to operate until I started looking into running one locally. It's honestly making me think that maybe trying to roll this out in phases starting with the NAS (while also doing some other infrastructure upgrades like looking at running cat 6a and swapping out my router from the ISP all-in-one to something that can run OPNSense paired with some WAPs), might be a better place to start. Then, if I can get some early successes under my belt, I can move onto the LLM arena and see how much time, money, and tears I want to spend getting that up and running. Oh, and thanks also for mentioning TiB; it sent me down a very interesting rabbit hole on the base 10 vs. base 2 byte measurement and how drive companies use the difference to pump up the number they get to advertise; I had no idea that accounting for the discrepancy in drive size, but is definitely not surprising.

Thank you! Honestly I am probably going way overboard myself (I think I've tried to convince myself that it might make sense given the likelihood of tariffs around the corner, but honestly might still end up downscaling to more like 10-20TB of storage and radically reduce my LLM expectations). And thanks also for the Crafty Controller rec, I hadn't heard of them and will definitely check them out!