I have DS920+, should I get mac mini for processing power?

I got 50TB synology NAS.

Main usage: -Plex media processing -Running *rr apps

Both plex and rr apps are slow on the DS920.

I’m asking for advice if I should get the mac mini for this use case or is it an overkill?

If yes, which ethernet port to get, 1 gig or 10? I don’t think there’s any files that would saturate 1 gig, but I might be short sighted