CenterRotation

Is there any easy way to migrate my appdata to my cache?

So I have an unraid set up for my local media. I use plex and other related dockers. I have a 1 TB Samsung m.2 as my cache but there really isnt anything on it. It currently has a 2% utilization. What should it being used for to improve my plex performance? I currentlyuse my RAM for transcoding when needed.

Do you have any experience with the M2 to SATA boards or should I just go with an 8 SATA port board and future-proof things?

I'm in the process of designing my first server that is mainly going to be for plex. I saw a special on some 18TB HDDs and was planning on starting with two of them (one being a parity drive). Is there anything wrong with starting out that way? I also am trying to decide if getting a motherboard with 8 SATA ports vs 6 SATA ports is worth it vs getting a M2 to SATA card down the road (especially if I plan on purchasing large capacity HDDs in the future). Any guidance would be helpful. Thank you very much in advance.