My setup is very influenced by consolidating multiple hosts to a single host. So far this setup has been extremely stable for me with the only quirk being the Truenas web gui initially loads very slowly if I haven’t accessed in a couple days. I assume it’s because all the memory for that has gone to swap to make space for caching.
Truenas has the primary focus of being a NAS. Running apps or VMs is more of a side thing. It can do these things fine, but because it’s not the primary focus it doesn’t get the same level of polish as the NAS aspects.
My personal solution is to run Proxmox as the host OS with a Truenas VM. Any other services I want to run get to live in VMs or LXC containers. For example all my docker services run across 3 VMs with a docker swarm setup.
Tailscale. You can make a free account and they have clients for most things. If you want to self host, Headscale.