Might not be the right answer to your questions but consider adding a 32GB RAM upgrade to the shopping list.

The NAS uses the unused ram space as cache for the file system and it’s made my SMB connections buttery smooth. Which I’m assuming you’ll need when accessing tons of files through your Macs.

In the past when I had the base amount of RAM on the Synology it would freeze all of Finder just opening a folder that had a ton raw photos in it and QuickLook was basically in unusable since it would take 45 seconds to load each image. Now I can fly through and quicklook photos as if it are plugged in like a flash drive this is on a 10 gig connection btw.

I was able to find compatible 2x16GB ECC sodimms on Amazon for a pretty ok price https://www.amazon.com/gp/product/B09G4MK264/ Been running good no hiccups since April of 2022.