Buying advice

[ed]

Hi there, and thanks for the kind words. Your plan actually makes good sense, and using the old TS431P as a snapshot backup target is a very practical way to extend its life. It is slow by modern standards, but for nightly replication and serving as a cold backup it is perfectly fine, and it keeps your main workloads away from aging SATA bays. For the new system, a Beelink ME Mini or Pro running ZimaOS is a strong option for Home Assistant, Immich, and general tinkering because you get proper Docker support, fast NVMe storage, and a clean interface that is easier for beginners than full Linux. The CPU choice matters only if you expect heavier AI driven workloads or large photo indexing later. The N95 handles Home Assistant and Immich very well at small to mid scale, but the N150 gives you noticeably more headroom and will feel healthier in three to five years if you start stacking more containers or larger libraries. If the price difference is not dramatic I would take the N150. As for Mini vs Pro, the hybrid Pro is nice but you do not strictly need its SATA bays since your QNAP already covers cold storage. The pure Mini gives you faster NVMe performance for apps, lower power use, and a simpler layout that matches what you described. So your flow becomes: QNAP TS431P as backup target, Beelink Mini for apps, Home Assistant, Immich, and future container experiments, and your main drives upgraded in stages so you stay within budget. This setup is quiet, flexible, and does not lock you into any one vendor.

Amazon links:
Beelink ME Mini
https://www.amazon.com/s?k=Beelink+ME+Mi...=ncmail-20
Beelink ME Pro
https://www.amazon.com/s?k=Beelink+ME+Pr...=ncmail-20