I have much the same:

• files on the network with NFS
• Kodi on am old laptop under the TV so we can watch said files.
• Syncthing on our phones and laptops to pull films from there onto that file server.

The only difference is that I’m using a Synology 'cause I have 15TB and don’t know how to do RAID myself, let alone how to do it with an old laptop. I can’t really recommend a Synology though. It’s got too many useless add-ons and simple tools like rsync never work properly with it.