I catch this one, should link you to other thread.
Totally your call. But you are already on a borderline setup, the risks outweigh the benefits IMHO
My little 7th gen i3 handle without problems 2 jails (Wireguard, Nextcloud) and an Alpine VM with ~15 containers. Excluding the gaming VM ( if you are not talking about retro gaming), don’t think you will have problem (but RAM can be a bit poor in this scenario, if multiple instance run together).
I started explore TN without, but now i have on both system, so for me Is a yes, better have it.
The situation Is exactly what u describe, hard to find a definitive answer. Recent thread about, take a look into It if you want
You can use 1 single disk striped for app and VM, and replicate data on the storage pool. Either a pci-ex to NVME adapter (the single NVME version!) to gain an extra sata (i have 2 xD)
(Btw, the bad disks can be imported/exported for local replication. Ok, not the best backup solution, but still a plus free backup)