TrueNAS on F4-425 split duties with mini PC or FrankeNAS that can do it all?

Ok so here is the situation, I was planning on combining my two NASs for backups and storage with my docker needs by moving to TrueNAS Community running on a Terramaster F4-425. I will go into that more later, but now let me describe the current homelab landscape. In no particular order: A PR4100 that runs Plex and stores the media for it. It also has a share for my proxmox ISOs, and is used as the backup for my proxmox; It does nothing else. I have a synology DS 216+II upgraded to 8gb of RAM, it runs my docker containers adgaurd, navidrome, freshrss, and n8n, with Neko being my next planned container (and the sorta reason for this post). I have a proxmox host running on a GMTek M5 with an AMD 5700U 32GB of ram, and a 1TB ssd, I don’t plan any changes to my proxmox host at the moment, but it runs my Nginx proxy manager, and a few VMs doing a lot. I have a few other devices but far less important and wont be changing.

Ok so the old(?) plan: Roughly I was planning on moving all docker and all NAS jobs into one NAS specifically I was thinking of getting a Terramaster F4-425 and loading TrueNAS Community onto it. Then using this one NAS to run my Plex, its storage, and run all the docker containers I have on my synology. I then planned on having this back itself up to another NAS at my parents house, which was planned to be the same hardware. Then at each location PCs can backup to the NAS. So we all have an almost 321 backup.

However last night I found something called Neko, something I have been looking for a while, a remote browser so I can always have the same tabs no matter what device I am on. But it dawned on me then, that I use a shit ton of tabs, like dozens open at a time, and I like it that way. But those tabs are going to use a ton of ram, this made me realize that if I did run neko on my new NAS, I would 100% be hitting a ram bottleneck, between navidrome, plex, the other docker containers, storage, backups, and everything else I fear I will overwork my poor new NAS. This has led me to this post, and finally I am getting to my main point.

Should I just get another mini PC to run docker stuff and plex, and just leave the new NASs to do NAS stuff like backups, replication, local shares, etc?

I would move plex and docker duties to my proxmox host, but it is nearly maxxed out most of the time. But this also sorta leads me to another question, should I just build a frankeNAS in something like 4 + 1 Bay DIY NAS Case as then I could make it whatever specs I want, and solves some issues I have read online about truenas and terramaster hardware (like lack of fan control, boot errors). Or I could do the terramaster plus, but doesn’t solve hardware issues like fan control.

Urg, sorry for the rambling post, I just see so many options, and I cant tell what is ‘best’. No matter what tho, something has to change, as currently only 2 of 5 family PCs have backups (to backblzae), and id like to up that to 5 of 5. And frankly I want to build something.

(disclosure the TLDR was made by AI then edited a bit by me, the main post is all me tho, no AI)
TL;DR: Planning to consolidate NAS + Docker (Plex, AdGuard, Navidrome, FreshRSS, n8n, + new Neko remote browser) onto a TrueNAS Community box on Terramaster F4-425, with offsite replica for 3-2-1 backups.

Problem: Neko + dozens of tabs will eat RAM; combined with Plex transcoding & other containers, the NAS will likely choke given the 16GB max.

Question:

  1. Split duties? Keep NAS purely for storage/backups/replication/shares, run Plex + all Docker on a separate mini PC?
  2. Or go all-in on a custom frankeNAS with high RAM/CPU to avoid Terramaster quirks (fan control, boot issues)?