Plex would probably make the process easier, im not sure on how to set it up myself though so couldnt really guide you on it.
ECC ram isnt necessary, its recommended because with ZFS an error in the memory could cause file corruption. For you use case it probably isnt necessary, depends if you care about your data enough to risk it. If its just stuff you can redownload or whatever I wouldnt care... You should have an extra backup for important stuff anyway.