I really do encourage experimenting more with NixOS. It’s the strange combination of feeling safer (because of the rollbacks) and more powerful (because of all the modules and packages already setup by the community)
I also spent a while using Proxmox. Almost went with it over TrueNAS. It was a little bit of a tossup, one is a good VM manager with ZFS support and the other good ZFS manger with VM support. I ended up just liking the interface better for TrueNAS, but both are certainly capable
I’m using a AMD Ryzen 7 3700X with 64GB of RAM for my main server. Looking at it right now (so just light background activity) the services are using ~3% of my CPU and 10GB of memory. Granted my ZFS cache is using 32GB of memory, I could tune that to use less, but I have enough headroom to make that fine
I opted to just use the Bitwarden service to avoid depending on my services to get my secrets for my services, so I haven’t tried running it, but I have heard good things about Vaultwarden. I’ll eventually try running that as a backup