I just put together a small setup very similar to what you mentioned.
A little Beelink Mini PC with the Intel N100 processor, 16g RAM and a 512 SSD and I hooked up two 8tb external drives. So far this is working really nicely!
The poor little N100 has been pegged at 100% for the last 3 hours as I run Immich to back up just over 22,000 photos & videos…but it’s just humming along and I’ll let it finish before I move on to something else.
Keep in mind the limitations of the hardware and I think you’ll have great little setup! I know I am enjoying this setup so far!
All in I am at just over $600, including the HexOS $99 special.