I tried OpenBSD back when my fastest computer was measured in Mhz. There wasn't very much software available for it at the time. Later I tried NetBSD (I was on gentoo at the time) and I really liked the ports system because it was easy to get all kinds of software, but I didn't see any sort of advantage at the time over Linux. Now the OS isn't terribly important, as long as it's Posix, has compilers, and doesn't force me to use Systemd. But the problem I've been having with the embedded hardware is they all have screwy binary blob bootloaders and it would be so much easier if I could just point them at a damn kernel. So I guess my second requirement is that the hardware not just work, but be decently supported by the OS without having to do stupid trickery like transplanting binaries from one system to another because I don't have a way to build the damn boot loader.
Heh, the homelab reddit is interesting. Lots of interesting hardware there.
I liked the size of those little Raspis, but they just didn't have enough RAM.
Your addiction doesn't seem as bad, you seem to have found a way to offload some of the hardware. I hold on to mine until the resale or usefulness drops to zero... I guess I could recycle some of it, but they're just so damned neat!
I might give it a shot in the near future. I just got Devuan working on here, so I'm not in a hurry to swap it for something else. But then I need more SD cards before I can try anything else, anyway.
I did Linux from Scratch about ten years ago. I learned a ton. I actually did a few more installs here and there of it. It really helped me to understand the boot process and getting different devices to work.
I've never been in a position where a system only had serial as an option. I've used it to capture kernel output, but not really interactively.
As for BSD, I like the GNU flavor shell utilities, the BSD ones have weird flags. Maybe I'll try out the Debian flavored BSD...