NAS drive recommendations?

[CharmPeddler]

I have some questions about optimizing my first NAS setup for my needs. 

QNAP TS-673 (not the "a" version).
I just purchased this (used) and is not yet set up. 


I have 6x 6 terabyte hard drives.
Three of the drives are wiped clean and ready for install. Two of them have data from my previous desktop that I used as individual JBOD type setup.

The NAS has spots for two m.2 SSDs.

I want to be able to run my own home lab on this with Plex, a few containers, including pie hole, maybe a Minecraft server for the family, and ability to run OwnCloud for family google photos and apple drive replacement. 

I plan on upgrading the memory from the stock two gigs to at least 32 gigs and maybe 64 gigs.

Should I buy an SSD for the drive slot number one {1ssd &5hdd}? My assumption is that will help with performance because the system will utilize that drive slot for the OS.
Combined with that, or possibly Alternatively, what can I actually do with the m.2 slots. Is that only for drive cashing? And do I have any direct control over it or will the system utilize it as it needs and I might or might not see benefits from it?

Or will the speeds be just fine with the WD Red HHDs?

[ed]

For your use case, having an SSD for the operating system will improve performance and speed up the overall NAS experience. Additionally, it can be used for caching, which will help with frequently accessed files and applications.

The m.2 slots on the QNAP TS-673 can be used for both caching and storage. If you plan to use it for caching, you can configure it in the Storage and Snapshots app, where you will be able to choose between read-only or read-write caching, depending on your needs. If you plan to use it for storage, you can configure it in the Storage Manager app, where you will be able to create a new storage pool that includes the m.2 drives.

Regarding the WD Red HDDs, they are reliable drives that are optimized for NAS use, and should provide decent performance for your needs. However, adding an SSD for caching or using it as the operating system drive will further improve performance, especially for frequently accessed files and applications.

Finally, upgrading the memory to at least 32 GB, as you mentioned, is a good idea for running multiple containers and applications simultaneously. It will also help with the overall performance of the NAS.