Welcome to the self-hosting trenches. Don't worry about the "burning yourself" part - in this hobby, we consider those "tactical lessons." Everyone has ah, "re-started" things at least a few times!
Actually, your plan isn't "not very smart"—it’s a classic move we call Decoupling Compute from Storage. It is the most future-proof way to build a Digital Fortress. By separating your "Brain" (HP Mini) from your "Vault" (Asustor), you ensure that if one fails, the other stays standing. This is a great move.
Here's how I see your planned setup:
**The Command Center: HP Z2 Mini - Xeon and Proxmox **
The Xeon 1245-v5 is a beast compared to that Celeron. Running Proxmox here is exactly the right call.
The Strategy: Use that M.2 drive for your Proxmox "Data" (the LXCs and VM boot drives). Services like Immich and Navidrome rely on fast databases; running them on an SSD on the Xeon node will make them feel lightning-fast.
The Gear: With 32GB of RAM, this is what I'd call an "Elite Node." You have plenty of head-room to grow.
**
The Vault: Asustor (Celeron N5105) **
TrueNAS SCALE is "Heavy Armor." Running it on a 2-bay Celeron is like putting tank treads on a scout bike - it’s overkill and eats up the limited RAM that Celeron has to offer.
The OS Choice: I’d strongly suggest OpenMediaVault 8 (OMV) for the Asustor. In my 2026 NAS OS Comparison Guide, I categorize OMV as the "Lightweight Tactical" choice. It’s built on Debian 13, is incredibly lean, and is the best way to turn low-power hardware into a rock-solid network drive. You’ve already tasted the freedom of a custom OS. Going back to ADM now will feel like a "vendor-lock-in" cage. OMV is the perfect middle ground...
**
How they talk to each other **
Wipe the Asustor, install OMV, and set up a simple NFS or SMB share. In Proxmox, you "mount" that network share. Your apps on the HP Mini will "see" the Asustor drives as if they were plugged in locally.
Is it a good idea? Yes . If you ever want more drive bays in the future, you just swap out the Asustor "Vault" for something bigger (like a 6-bay DIY build or a UGREEN box), and your HP Mini "Command Center" never even has to go offline.
I recently broke down the "Battle Card" for why OMV is the king of low-power storage nodes in 2026. You might find the comparison table helpful for your specific hardware: NAS OS Comparison
It's literally based off the NAS comparison guide I posted... This is like a text book way to move forward for someone. My solution is like a giant all in one+a NAS, but a lllooottt of people have a decoupled solution.
One of the beautiful things about self-hosting; do what you want.